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Background The role of Th1 and Th2 mediated cytokine responses in the pathogenesis of Cryptococcus neoformans infection in organ transplant recipients has not been defined. Methods We assessed cytokine levels in the sera and CSF collected prospectively at the time of diagnosis of infection in 25 transplant recipients with cryptococcosis. Serum levels were compared with those in healthy individuals and transplant recipients without cryptococcosis. IFN-γ or IL-12 (Th1)/IL-10 (Th2) ratio

A 56-year-old previously healthy man had two episodes of unexplained pancreatitis in the setting of constitutional symptoms, recurrent palsy of the right seventh cranial nerve, and bilateral parotitis. Chest radiography revealed marked bilateral hilar lymphadenopathy, and sarcoidosis was diagnosed by bronchoscopy with transbronchial biopsy showing noncaseating granulomas. The pancreatitis and sarcoidosis responded to corticosteroid therapy but recurred after corticosteroid dosage was reduced. Retreatment with a higher dosage of corticosteroids led to resolution of pancreatitis; 3 months later, the patient remained well and without further recurrence of pancreatitis while taking the higher dose of corticosteroids. Clinically significant pancreatitis should be included as an unusual manifestation of sarcoidosis, and corticosteroid therapy should be considered in the management of pancreatitis associated with sarcoidosis.

The Platelia galactomannan enzyme immunoassay is a commercially available nonculture method for diagnosing invasive aspergillosis. Recently, steps have been taken to improve sensitivity; specifically, a low (0.5 to 0.7) galactomannan index (GMI) value to determine positivity has been validated by multiple groups. We evaluated the intra-assay and interassay reproducibility at low index levels using three different kit lots on three different days in three different microbiology laboratories. Clinical and spiked sera were blinded and sent with galactomannan enzyme immunoassay (EIA) kits to the participating laboratories. We also prospectively collected data on all galactomannan EIAs performed between 1 September 2003 and 21 July 2004 at the University of Washington Medical Center microbiology laboratory to assess reproducibility of clinical samples analyzed in “real time.” From the multilaboratory study, a total of 836 results were available for evaluation. Reproducibility was excellent between laboratories and on different days. Significant variability was seen between runs/lots, which may in part be associated with different threshold control values in different kits. Among the 1,410 clinical samples that were prospectively analyzed, 168 (90%) were confirmed to be positive on repeat testing (GMI, ≥0.5). Among the 19 (10.2%) initially positive samples not confirmed on repeat testing, the majority had a GMI at the threshold of the assay (between 0.5 and 0.7). Our findings suggest that the Platelia galactomannan immunoassay has good reproducibility. However, changes in GMI levels when different kit lots are used, and single samples with low-positive (GMI of 0.5 to 0.7) indices, should be interpreted with caution.

We report a case of Chagas' cardiomyopathy confirmed in a patient after heart transplantation. The patient initially presented with symptoms of congestive heart failure and was found to have positive serology for prior Trypanosoma cruzi infection. Despite optimal medical management, the patient had deterioration of his cardiac function and he underwent heart transplantation. Pathology examination of the explanted heart confirmed Chagas' cardiomyopathy. The cardiac sequelae of Chagas' disease include arrhythmias, aneurysm, thromboembolism, cardiomyopathy, and sudden death. We review the epidemiology, cardiac pathology, and evaluation of patients with Chagas' cardiac disease. We discuss the clinical features of Chagas' cardiomyopathy and available treatments including cardiac transplantation.

Chronic renal dysfunction is common in non-renal solid organ (SOT) and hematopoietic stem cell transplant (HSCT) recipients and is commonly attributed to calcineurin inhibitor toxicity, often without renal histopathologic evaluation. Polyomavirus nephropathy (PVN) is an important cause of allograft dysfunction in kidney transplant recipients but has rarely been reported in native kidneys of non-renal transplant recipients. We report the clinical, pathologic and virologic features of PVN in native kidneys of two allograft recipients. In both, severe renal dysfunction was accompanied by histopathologic evidence of PVN, including characteristic viral inclusions by routine stains, immunohistochemistry and electron microscopy. High levels of BK virus (BKV) DNA were detected in kidney tissue of patients using BKV-specific polymerase chain reaction (PCR). In 1 patient, high levels of BKV DNA were detected in plasma and urine, and administration of low-dose cidofovir was associated with clearance of BK viremia. These results extend the populations in which PVN has been documented in native kidneys to include heart and stem cell transplant recipients, and suggest that cidofovir has activity against BKV in vivo. Studies to define the incidence and potential contribution of PVN to chronic renal dysfunction commonly attributed to calcineurin inhibitor toxicity in non-renal transplant recipients are warranted.

Objectives To determine the rate of gram-positive localizations and whether repetitive cultures demonstrate consistent localization of gram-positive bacteria in patients with chronic prostatitis symptoms. Methods We repeated localization cultures at different visits for untreated patients with chronic prostatitis symptoms. Results A total of 470 patients with chronic prostatitis had lower urinary tract localization cultures done. Ten-fold increases in the concentrations of gram-positive bacteria were noted when the postprostatic massage (VB3) or expressed prostatic secretions cultures were compared with first-void urine (VB1) cultures from 29 patients (6%). This was comparable to the 7% rate of gram-negative chronic bacterial prostatitis. We studied 49 patients who had undergone 130 repeated localization studies (median 2, range 2 to 4). Repeatedly negative studies were found in 20 patients, including 19 who each had undergone two studies and 1 who had undergone four studies. Of 9 patients who each had undergone three or four studies, 9 demonstrated localization of at least one gram-positive species. Of the 29 patients with gram-positive localizations, 27 (94%) did not have consistent localization of the gram-positive species. Conclusions Patients with chronic prostatitis demonstrated localization of gram-positive bacteria, but the results were seldom reproducible in untreated patients. Gram-positive localizations may represent nonpathogens, transient bacterial colonization of the lower urinary tract, or intermittent shedding of prostatic pathogens. The limitations of traditional cultures highlight the need for better diagnostic approaches and improved recommendations for antimicrobial therapy.

The incidence and impact of cytomegalovirus (CMV) disease that occurs despite CMV prophylaxis among liver transplant recipients have been incompletely defined.The incidence and risk factors for CMV disease during the first posttransplant year in a cohort of liver transplant recipients who received antiviral prophylaxis with oral ganciclovir were retrospectively analyzed using Cox proportional-hazard regression models.CMV disease developed in 19 of 259 recipients (7% [95% confidence interval 0.04-0.11]) at a median of 4.5 months posttransplant, included syndrome (63%) or tissue-invasive disease (37%), and was independently associated with an increased risk of mortality during the first posttransplant year (hazard ratio 14 [95% confidence interval 3.8-54], P=0.0007). The incidence was higher (10/38 [26%] vs. 8/180 [4.5%], P0.0001) in seronegative recipients (R-) of an organ from a seropositive donor (D+) compared with seropositive (R+) patients, respectively. D+R- status was the only variable significantly associated with CMV disease in multivariate analysis.Late CMV disease develops in a substantial proportion of D+R- recipients after prophylaxis is discontinued, is not accurately predicted by patient factors, and is associated with increased mortality. New strategies to identify D+R- patients at risk and to reduce the incidence and impact of late CMV disease in this group are warranted.

The purpose of the present study was to characterize BK viremia in a large cohort of HSCT recipients who underwent longitudinal plasma sampling. Specifically, we sought to determine the risk factors for and the incidence, duration, and quantitative aspects of BK viremia. We also correlated BK viremia with hemorrhagic cystitis that occurred after platelet engraftment, thereby eliminating the confounding influence of low platelet counts and the residual effects of chemotherapy. Patients and methods. The study population was a prospective cohort of 132 consecutive adult patients who received non–T cell–depleted allogeneic or autologous HSCT in 1998. This cohort represented an unselected, contemporaneous population of recipients of myeloablative HSCT. The entire cohort was retrospectively evaluated by testing for BK viremia, as well as by reviewing the clinical records of the patients to search for evidence of hemorrhagic cystitis. Because adenovirus infection has also been proposed to contribute to the development of hemorrhagic cystitis, the laboratory records of patients with hemorrhagic cystitis were reviewed for information indicating the presence of adenovirus in urine, as determined by culture and direct fluorescent antibody assay, from 7 days prior to hemorrhagic cystitis until the last day of the event. Testing for adenovirus was performed by clinicians for clinical diagnostic reasons. Testing of urine samples for BK virus was only occasionally performed in 1998, when the present study took place. The study received institutional review board approval. Plasma samples were collected on a weekly basis, starting from the day of transplantation until approximately day 100 after transplantation. The samples were frozen at 80� C and were stored for future analysis. The plasma samples of patients with hemorrhagic cystitis, which were drawn at the time of the event, were analyzed by PCR for adenovirus DNA. PCR conditions were reported elsewhere [4]. The primers and probe that were used for the detection of BK virus were BK-F (AAA TGC CTT AAT CTA AGC TGA CAT AG), BK-R (GCA AGG AAT GGC CTA TTT GTT CCA AA), and BKProbe (FAM-TGC AAG GGC AGT GCA CAG AAG GCTTAMRA). Two assays were performed for the detection of adenovirus DNA; one assay detects subgroups A and F (Adeno-AF PCR), and one detects subgroups B,C, D, and E (Adeno-BCE PCR). The primers that were used for the first assay were HexonA-F (CCG GKC TGG TGC AAT TCG), HexonA-R1 (CGATCCACGGGCACAAA), HexonF-1 (TGTTYGAAGTTTT CGACGTYGT), and HexonF-2 (SAGGTAGACGGCCTCGATGA); the probes that were used were HexonA-P (FAM-CCACGGACACCTACTTCACCCTGGG-TAMRA) and HexonF-P

Helcococci have previously been associated with the colonization of ulcers and infections of the skin and soft tissues. We describe a case of prosthetic joint infection due to a previously undescribed organism that is genetically most closely related to Helcococcus.

Studies have shown that vancomycin broth enrichment is superior to direct plating for the detection of vancomycin-resistant enterococcus (VRE), but vancomycin selective broth is not generally commercially available. We developed an easy-to-prepare VRE selective differential broth and compared it to direct plating on bile esculin azide (BEA) agar for the isolation of VRE from fecal samples. A total of 528 consecutive rectal swabs and stools were inoculated onto BEA agar and into BEA broth with vancomycin at a concentration of 15 μg/ml (BEA VAN 15μg/ml broth). After 1 to 2 days of incubation, broths were subcultured to BEA VAN 6μg/ml agar. Bile esculin-positive colonies from the direct and broth subculture plates were evaluated for the presence of VRE by standard microbiological techniques. Addition of the broth enrichment step led to the detection of significantly more VRE isolates than did direct plating alone (28 versus 18 VRE isolates, respectively). In all, 30 VRE strains were isolated from 29 cultures, all of which were Enterococcus faecium . MICs of vancomycin ranged from 32 μg/ml ( n = 2) to > 256 μg/ml ( n = 28). Twenty-two VRE isolates were available for further testing: sixteen exhibited a VanA phenotype and six were of the VanB phenotype. van genotypes were in agreement with phenotypes for all VRE isolates except one, which could not be genotyped. The broth method also resulted in significantly fewer bile esculin-positive, non-VRE isolates requiring further workup. We have thus developed an easily prepared vancomycin selective differential broth that is significantly more sensitive and specific in the detection of VRE than is direct fecal plating to BEA agar.

BK virus-associated nephropathy (BKVN) has become recognized as an important cause of allograft dysfunction in renal transplant recipients and despite reduction in immunosuppression, 30–40% of recipients ultimately progress to allograft loss. Cidofovir is an antiviral agent that demonstrates in vitro activity against murine polyomavirus and has been proposed for treatment of BKVN in renal allograft recipients. We describe the clinical course, renal function, serial renal histology and urine and blood viral load measurements in two consecutive patients with refractory BKVN who were treated with low-dose cidofovir (0.25 mg/kg IV). In each case, renal dysfunction and BK viral load progressed despite reduced immunosuppression, and persistent BK virus infection was documented in serial renal allograft biopsy specimens. Administration of low-dose cidofovir was associated with clearance of BK virus DNA from blood and allograft, and stabilization of renal function in both patients, without significant toxicity. These preliminary data suggest that low-dose cidofovir may be tolerated, even among renal transplant recipients with significant renal dysfunction due to BKVN. Prospective, controlled trials are warranted to further define the optimal dose, toxicity and potential role of cidofovir in renal transplant recipients with BK virus nephropathy.

Clostridium difficile is one of the most frequent causes of nosocomial gastrointestinal disease. Risk factors include prior antibiotic therapy, bowel surgery, and the immunocompromised state. Direct fecal analysis for C. difficile toxin B by tissue culture cytotoxin B assay (CBA), while only 60 to 85% sensitive overall, is a common laboratory method. We have used 1,003 consecutive, nonduplicate fecal samples to compare six commercially available immunoassays (IA) for C. difficile detection with CBA: Prima System Clostridium difficile Tox A and VIDAS Clostridium difficile Tox A II, which detect C. difficile toxin A; Premier Cytoclone A/B and Techlab Clostridium difficile Tox A/B, which detect toxins A and B; and ImmunoCard Clostridium difficile and Triage Micro C. difficile panels, which detect toxin A and a species-specific antigen. For all tests, Triage antigen was most sensitive (89.1%; negative predictive value [NPV] = 98.7%) while ImmunoCard was most specific (99.7%; positive predictive value [PPV] = 95.0%). For toxin tests only, Prima System had the highest sensitivity (82.2%; NPV = 98.0%) while ImmunoCard had the highest specificity (99.7%; PPV = 95.0%). Hematopoietic stem cell transplant (HSCT) patients contributed 44.7% of all samples tested, and no significant differences in sensitivity or specificity were noted between HSCT and non-HSCT patients. IAs, while not as sensitive as direct fecal CBA, produce reasonable predictive values, especially when both antigen and toxin are detected. They also offer significant advantages over CBA in terms of turnaround time and ease of use.

We developed a rapid genotypic assay to differentiate the germ tube-positive yeasts Candida albicans and Candida dubliniensis . Fluorescently labeled nucleic acid probe binding and subsequent denaturation from the target site in the PCR amplicons produced characteristic peak melting temperatures ( T m ) that identified each species. Peak T m s of C. albicans ( n = 69) and C. dubliniensis ( n = 28) isolates produced in the presence of their respective probes were 61.04 ± 0.64°C and 60.52 ± 1.01°C (averages ± standard deviations). No signal was generated when the C. albicans or C. dubliniensis probes were tested against DNA from their counterparts. Both probes reacted with Candida tropicalis DNA, but the T m was 51.85 ± 0.05°C with the C. albicans probe and 51.92 ± 0.10°C with the C. dubliniensis probe, differentiating C. tropicalis DNA from C. albicans and C. dubliniensis. A novel hybrid probe was designed to identify both species in a single reaction based on a 4°C difference in peak T m s. Our assay is rapid (≤2 h) and allows reliable detection and differentiation of the two germ tube-positive Candida spp.

Ganciclovir-resistant (GanR) cytomegalovirus (CMV) is an emerging clinical problem in organ transplant recipients, particularly recipients of kidney and pancreas and lung transplants. GanR CMV, a late posttransplantation complication, is observed predominantly among CMV-seronegative recipients of organs from seropositive donors, especially among recipients receiving intensive immunosuppression and having prolonged exposure to ganciclovir. Given the limitations of current diagnostic methods, if GanR CMV is clinically suspected, empirical treatment with intravenously administered foscarnet should be used in conjunction with reductions in immunosuppressive therapy and possibly CMV hyperimmune globulin. Better diagnostic tools and newer, less-toxic antiviral agents with different mechanisms of action are urgently needed to decrease the morbidity associated with this complication in organ transplant recipients.

We report a case of Candida dubliniensis fungemia in a solid organ transplant patient, which, to our knowledge is the first such case in this patient population. C. dubliniensis is a recently described, emerging fungal pathogen, thus far, found in AIDS and a limited number of other immunosuppressed patients. It is of interest and concern because it can be misidentified as C. albicans and it may be resistant to azole antifungal agents. This case illustrates the need to be aware of emerging pathogens in new host populations and that new techniques used to identify yeast species may provide more accurate identification.

Species-specific polymorphisms in the noncoding internal transcribed spacer 2 (ITS2) region of the rRNA operon provide accurate identification of clinically significant yeasts. In this study, we tested the hypothesis that ITS1 noncoding regions contain diagnostically useful alleles. The length of ITS1 region PCR products amplified from 40 species (106 clinical strains, 5 reference strains, and 30 type strains) was rapidly determined with single-base precision by automated capillary electrophoresis. Polymorphisms in the PCR product length permitted 19 species to be distinguished by ITS1 alone, compared with 16 species distinguished by using only ITS2. However, combination of both ITS alleles permitted identification of 30 species (98% of clinical isolates). The remaining 10 species with PCR products of similar sizes contained unique ITS alleles distinguishable by restriction enzyme analysis. DNA sequence analysis of amplified ITS1 region DNA from 79 isolates revealed species-specific ITS1 alleles for each of the 40 pathogenic species examined. This provided identification of unusual clinical isolates, and 53 diagnostic ITS1 sequences were deposited in GenBank. Phylogenetic analyses based on ITS sequences showed a similar overall topology to 26S rRNA gene-based trees. However, different species with identical 26S sequences contained distinct ITS alleles that provided species identification with strong statistical support. Together, these data indicate that the analysis of ITS polymorphisms can reliably identify 40 species of clinically significant yeasts and that the capacity for identifying potentially new pathogenic species by using this database holds significant promise.

Among hematopoietic stem-cell transplant (HSCT) recipients, cytomegalovirus (CMV) disease before engraftment is rare but often fatal, and cell-based diagnostic tests have low sensitivity in this clinical setting. We used the quantitative real-time polymerase chain reaction (PCR) assay to test for CMV DNA in plasma samples from 15 HSCT recipients who developed CMV disease before engraftment and from 33 matched control patients. CMV DNA was detected in plasma in 14 (93.3%) of the 15 patients who had CMV disease before engraftment, compared with 5 (15.2%) of 33 control patients (P.001). CMV DNA was detected a median of 13 days before the onset of CMV disease (range, 0-35 days). The maximum CMV virus load in plasma was1 log(10) higher among case patients than among control patients (median, 1700 [range, 50 to 5.5x107] vs.50 [range,50-350] CMV DNA copies/mL plasma, respectively; P.001). Quantitative PCR for CMV DNA in plasma appears to be useful for the identification of HSCT recipients at risk for CMV disease before engraftment.

Using molecular typing methods, we confirmed an outbreak ofStenotrophomonas maltophiliaamong bone marrow transplant patients. The likely source was a healthcare worker who may have washed with moisturizer instead of soap between patients. Hospital epidemiologists need to go beyond antibiograms when evaluating outbreaks and be vigilant about all aspects of hand washing.

Early diagnosis of Epstein-Barr Virus (EBV)-associated posttransplant lymphoproliferative disease (PTLD) is important because many patients respond to reduction in immunosuppression, especially if PTLD is detected at an early stage. Previous studies have found elevated EBV DNA levels in blood from patients with PTLD, but these assays required isolation of cellular blood fractions and quantitation. We evaluated the presence of cell-free EBV DNA in serum from solid-organ transplant recipients as a marker for PTLD. Five of 6 transplant recipients with histopathologically documented PTLD had EBV DNA detected in serum at the time of diagnosis (sensitivity = 83%), compared with 0 of 16 matched transplant recipients without PTLD (specificity = 100%) ( P < 0.001 [Fisher’s exact test]). Furthermore, EBV DNA was detected in serum 8 and 52 months prior to the diagnosis of PTLD in two of three patients for whom stored sera were analyzed. Detection of EBV DNA in serum appears to be a useful marker for the early detection of PTLD in solid-organ transplant recipients. Further studies to define the role of such assays in evaluating solid-organ transplant patients at risk for PTLD are warranted.

Listeria monocytogenes is a well-recognized cause of bacteremia and meningitis in immunocompromised individuals, including recipients of solid organ transplants, but has only rarely been reported following orthotopic liver transplantation (OLT). Most previously reported cases of listeriosis occurred months to years following liver transplantation; we describe a case of listeriosis that occurred within 1 wk of liver transplantation, shortly after discontinuation of trimethoprim-sulfamethoxazole prophylaxis, and review the English literature on Listeria infection after OLT. The patient developed abdominal pain and fever that suggested a bile leak, but was definitively diagnosed with Listeria infection by blood culture. The infection was successfully treated with 3 wk of intravenous ampicillin. We conclude that serious systemic infection with Listeria monocytogenes is uncommon following OLT, may occur early in the postoperative period, and responds well to treatment with high dose ampicillin.

BACKGROUND We report the clinical course of a patient who developed fever, hypoxia, and bilateral pulmonary infiltrates two and a half years after orthotopic liver transplantation (OLT) for cirrhosis due to hepatitis C. The patient had a history of hepatitis C-associated vasculitis manifested by purpuric skin rashes, renal abnormalities, and elevated cryoglobulins, and was receiving interferon-alpha at the time of presentation. RESULTS The results of bronchoscopy with bronchoalveolar lavage were unrevealing, and open lung biopsy revealed active small vessel vasculitis. The patient responded dramatically to plasmapheresis and the addition of high-dose corticosteroids with resolution of hypoxia, pulmonary infiltrates, and glomerulonephritis. This is, to our knowledge, the first report of the successful treatment of hepatitis C-associated pulmonary vasculitis after OLT. CONCLUSIONS We conclude that hepatitis C-associated pulmonary vasculitis should be included in the differential diagnosis of a patient presenting with fever, hypoxia, and pulmonary infiltrates after OLT for hepatitis C. Treatment with plasmapheresis and high-dose corticosteroids may be effective in patients with this disorder.

Aim Late onset CMV disease is an important complication in CMV seronegative transplant recipients (R-) receiving livers from CMV positive donors (D+) after discontinuation of antiviral prophylaxis. Predicting the risk of developing CMV disease will allow for better targeted therapy. Natural Killer (NK) cells may play a role in modulating CMV disease. Increased number of NK activating killer cell immunoglobulin-like receptors (KIR) genes has previously been associated with a lower rate of CMV disease in kidney transplant recipients. Methods We assessed the relationship between recipient, or donor, KIR genotype and the incidence of CMV disease in a cohort of consecutive CMV D+R- liver transplant recipients (n = 170). All recipients received 3 months of standard anti-viral prophylaxis and were followed for 1 year post transplant or until death. Fifty six patients (33%) developed CMV disease post transplant. HLA and KIR genotyping of recipients and donors was performed by SSP and SSO methods respectively. Results We observed no association between the number or type of recipient, or donor, activating KIR genes and the incidence of CMV disease. There was a trend towards a lower incidence of CMV disease in patients who had 1) 3 recipient inhibitory KIR genes (2DL1, 2DL2, 2DL3) compared to patients with only 1 or 2 genes (27.8% vs. 35.7%), 2) licensed donor NK cells with cognate recipient HLA-C ligands (28.8% vs. 39.3%), p > 0.05 for all comparisons. Conclusions Our results do not support a role for activating KIR in the control of CMV disease in the current setting. Inhibitory KIR may play a role in controlling CMV disease in liver transplant recipients and should be further explored in a larger study.

Peripheral blood eosinophil counts and serum levels and in vitro production of eosinophilopoietic cytokines were assessed before and at frequent intervals after diethylcarbamazine treatment of Bancroftian filariasis. Eosinophil counts peaked at day 7 after the start of treatment (359% +/- 118% of pretreatment levels) and declined to pretreatment levels by day 17. Serum interleukin (IL)-5, undetectable in 14 of 15 patients before treatment, rose sharply but transiently, with peak levels (32 +/- 7 pg/mL) 2 days after diethylcarbamazine treatment. Granulocyte-macrophage colony-stimulating factor and IL-3 were not detectable in serum at any time. In vitro mitogen-induced IL-5 levels decreased significantly in 7 of 9 patients 3 days after treatment when serum IL-5 was at near-peak levels. By day 10 IL-5 values increased in 8 of 9 patients compared with treatment values (P < .02). These data define the temporal relation between serum IL-5 levels and the subsequent development of eosinophilia and suggest that lymphocytes are the source of IL-5.

Despite receiving antiviral prophylaxis, many lung transplant recipients develop cytomegalovirus infections during the year after transplant. This randomized trial assigned 136 lung transplant reci...

Vancomycin MIC creep has been reported by some institutions but not confirmed in large surveillance studies. We evaluated the possible occurrence of MIC creep when testing vancomycin and daptomycin against methicillin (oxacillin)-resistant Staphylococcus aureus (MRSA) by using precise incremental reference MIC methods. Nine hospitals (one in each U.S. census region) randomly selected bloodstream MRSA strains (target, 40/year) from 2002 to 2006. MICs were determined by the reference broth microdilution method using incremental dilutions (eight for each log 2 dilution step). Isolates for which vancomycin MICs were >1 μg/ml were typed by pulsed-field gel electrophoresis (PFGE). The vancomycin MIC mode was either 0.625 μg/ml (for eight hospitals) or 0.813 μg/ml (for one hospital), and vancomycin MIC results for 72.9% of strains were between 0.563 and 0.688 μg/ml. No yearly variation in the central tendency of vancomycin MICs for the wild-type population in any medical center was observed; however, when data were analyzed by the geometric mean statistic, vancomycin MIC increases (at three sites) and declines (at three sites) were observed. The daptomycin MIC mode varied from 0.156 μg/ml (2003 to 2005) to 0.219 μg/ml (2002 and 2006), and MIC results for 83.5% (80.3 to 89.2% in each of the centers) of isolates fell between these values. Among PFGE-typed strains, 43 of 55 (78%; from seven hospitals) showed a pattern consistent with that of the USA100 clone, which was represented by all strains from two hospitals and 64 to 88% of strains from five other medical centers; only one strain (2%) was USA300. In conclusion, the perception of MIC creep may vary according to the methods used to analyze the data. Geometric mean MIC data revealed a possible, very-low-level MIC creep at three of nine sites over the 5-year period, which was not evident using modal MICs or the data from all nine hospitals (+0.02 μg/ml). The occurrence of isolates for which the vancomycin MIC was >1 μg/ml was very unusual, with no increased trend, but these organisms were usually clonal (USA100).

We report a case of severe pseudomembranous colitis due to a toxin A − B + strain of Clostridium difficile in an immunosuppressed patient and discuss the implications for diagnostic testing in suspected C. difficile -associated diarrhea.

To understand the role of the eosinophilopoietic cytokine IL-5 in humans, the posttreatment eosinophilic response in a group of microfilaria (mf)-positive patients with onchocerciasis (n = 10) was examined before and after treatment with diethylcarbamazine (6 mg/kg for 7 d). Sequential blood samples were assessed at 24 and 1 h before treatment (baseline values), then at frequent intervals over the next 14 d. Symptom scores, skin microfilariae (mf), and peripheral blood eosinophil counts were recorded as a function of time after treatment, and serum levels of IL-5 were quantitated by a highly sensitive (sensitivity greater than or equal to 20 pg/ml) monoclonal-based ELISA. Pretreatment eosinophil counts ranged from 240 to 1,186 eosinophils/microliter (geometric mean, 675), and the mf counts from 10 to 218 per mg skin (geometric mean, 79). After an initial decline in the peripheral eosinophil count to 28 +/- 8% of pretreatment levels at 8 h after beginning treatment, the eosinophil counts steadily increased over the next 2 wk, reaching a maximum at 14 d (257 +/- 38% of pretreatment levels). Serum levels of IL-5 rose sharply from pretreatment levels to a peak of 70.5 +/- 11 pg/ml by 24 h after treatment. Serum IL-5 remained elevated over the next 2-3 d and declined toward baseline by approximately 6 d after treatment, at which time the eosinophil levels were steadily increasing. IL-3 and granulocyte macrophage colony-stimulating factor, two other cytokines implicated in eosinophilopoeisis, were not detectable in the serum at any time before or after treatment. The rise in serum IL-5 before the posttreatment eosinophilia seen in this group of patients with onchocerciasis demonstrates a temporal relationship between IL-5 and the subsequent development of eosinophilia and implicates IL-5 as an important mediator of eosinophilia in humans.

A27-YEAR-OLD PREVIously healthy migrant farm worker presented with progressive bilateral lower extremity weakness that had developed during the preceding month.Hisphysicalexaminationresultswerenotableforbilaterallower extremity weakness (right greater than left), clonus in the right foot, diminished sensation to pinprick from T9 through S1 bilaterally, and incontinence of bowel and bladder. He was also noted to have superficial white onychomycosis on multiple digits (Figure 1). Magnetic resonance imaging of the spine (Figure 2) showed a 10914-mm intramedullary lesion centered at C7-8, with extensive T2 hyperintensity and marked expansion of the entire spinal cord. Computed tomographic scans of his chest and head were normal. Analysis of the cerebrospinal fluid showed a white blood cell count of 159 cells/µL (92% lymphocytes, 7% macrophages, and 1% neutrophils), red blood cell count of 340 cells/µL, glucose level of 55 mg/dL (3.05 mmol/L), and protein level of 33 mg/dL. A gram stain of the cerebrospinal fluid was normal and culture yielded no organisms. A biopsy specimen of the spinal cord lesion showed granulomatous inflammation with budding yeastlike organisms seen on Gomori methenamine silver staining; these were identified as Histoplasma capsulatum on culture. The possibility of an underlying immunodeficiencywasraisedbythe diagnosis of histoplasmosis of the central nervous system (CNS) in a young, otherwise healthy man and the presence of superficial white onychomycosis. This form of onychomycosis is caused by fungal invasionofthesuperficiallayersofthe nailplateandisoftenassociatedwith immunosuppressionandwithAIDS in particular. 1 He was indeed found to be positive for the human immunodeficiency virus and had a CD4 count of 34 cells/µL and a viral load of 42000 copies/mL. Ourpatientpresentedwithanisolated spinal cord lesion as his initial manifestation of both histoplasmosisandAIDS.Therearepreviouscase reports of histoplasmosis presenting with isolated CNS disease, typically in the setting of local recurrenceattributedtotherelativelypoor penetrationofantifungalsintothecerebrospinal fluid. 2 Clinical syndromes of CNS histoplasmosis includechronicmeningitis,focalbrain or spinal cord lesions, stroke syndromes,andencephalitis.Patientsare typically,butnotexclusively,immunocompromised. The optimal managementofCNShistoplasmosisisunclear, but given the high rates of treatment failure (approximately 20%) and relapse (approximately 40%),anaggressiveapproachisusually recommended. 3 Our patient received corticosteroids for his severe cord edema, liposomalamphotericinB,andhighly active antiretroviral treatment. His condition improved; 1 month later he had regained some use of his left leg but not of his right.

Reconstitution of adaptive T-cell responses to human cytomegalovirus (CMV) is critical to protection from CMV disease following hematopoietic stem cell (HSCT) or solid organ transplantation (SOT). However, there is an incomplete understanding of which CMV antigens and epitopes are most crucial to providing protective responses. The functional status of cytotoxic T-lymphocyte (CTL) populations recognizing cytomegalovirus IE-1 and pp65 polypeptides was investigated in PBMC from either HSCT or SOT recipients. Our previous finding of differing levels of degranulation between CMV IE1 and pp65/pp50 specific T-cells was complicated by the possibility that differences were epitope and/or HLA-specific. We generalized the approach using a combined flow-based CD107a/b degranulation/mobilization and intracellular cytokine (ICC) assays using peptide libraries as antigens. These assays indicated that a significantly higher proportion of pp65-specific CTLs were in a more mature functional state compared to IE-1-specific CTLs. Degranulation/multicytokine ICC assays also indicated that a significantly higher proportion of the pp65-specific versus IE-1-specific CTLs secreted both IFN-γ and TNF-α, in addition to possessing greater cytotoxic potential. These results support our earlier findings of functional differences between CTLs recognizing individual epitopes within the IE-1 and pp65 antigens in HSCT recipients, and extend them to a broader array of HLA-restricted responses to those antigens. A report that a subset of HIV-1 specific CTLs capable of producing both IFN-γ and TNF-α was associated with improved cytotoxic activity prompted us to investigate whether degranulation, a functional correlate of cytotoxicity, was positively associated with dual cytokine production and predicted differences between IE1 and pp65-specific CD8+ T-cells. A higher proportion of pp65-specific compared to IE1-specific T-cells were present in the trifunctional IFN-γ+,TNF-α+, CD107+ population (p=0.008) in HSCT recipients. We have extended these findings to investigate the role of donor CMV status in terms of functional maturity of CMV-specific T cell response in transplant recipients. T cell maturation/function may act as a mechanistic correlate to the survival advantage of recipients receiving a stem-cell graft from CMV sero-positive donors. These principles have also been applied to investigations of a high risk population of sero-negative recipients of a sero-positive liver allograft. Data from this study will also be reviewed in the context of the model of trifunctional T cells being indicative of enhanced protective capacity against CMV disease and associated with survival.

To the Editor. —Dr Westfall and colleagues 1 raised ethical concerns regarding the frequent personal use of drug samples by medical personnel. We report on Clostridium difficile —related diarrhea as a complication of this practice in medical house staff who have ready access to pharmaceutical samples of antibiotics and frequent exposure to the organism in the hospital setting. A 26-year-old, otherwise healthy medical resident with self-diagnosed sinusitis began a course of amoxicillin-clavulanate samples that he had received from a pharmaceutical company representative. Ten days later he experienced crampy abdominal pain and watery diarrhea. He suspected C difficile —related diarrhea and empirically began a course of metronidazole until stool studies demonstrated C difficile by toxin assay (cultures for enteric pathogens were negative). His diarrhea responded to 10 days of oral metronidazole, but he experienced a relapse 4 weeks later that also responded promptly to re-treatment with the same regimen. A 28-year-old, otherwise