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This prospective study was designed to determine the role of antineutrophil cytoplasmic autoantibodies (ANCA) in HIV-infected patients. Immunofluorescence tests (IFT) and enzyme-linked immunosorbent assays (ELISA) were applied to sera of 199 consecutive outpatients. In the IFT 20% were positive. An atypical ANCA pattern was demonstrated in 67% of these, 33% revealed a perinuclear staining (pANCA). Specific ELISA revealed proteinase 3 (n = 2), myeloperoxidase (n = 1), lysozyme (n = 2), lactoferrin (n = 1), cathepsin G (n = 1), and human leukocyte elastase (HLE, n = 6). The target antigen remained unidentified in 26 patients. Perinuclear ANCA-positive patients showed atypical antigens in eight of 13 cases; all six patients with anti-HLE revealed a pANCA pattern. The antigens of atypical ANCA-positive patients remained unidentified in 21 of 26 (81%) cases. No signs of vasculitis were present in the ANCA-positive patients. ANCA are frequently found in the sera of HIV-positive patients. They bind to a variety of antigens. No correlation was found between ANCA positivity and autoimmune or opportunistic diseases.

Failure to downregulate resting energy expenditure (REE) as an adaption to anorexia or malabsorption is often stated as the major cause of weight loss in individuals with AIDS. In a prospective study, REE was compared with weight changes in HIV-infected patients. The impact of altered body composition on REE was reassessed by critical review of the literature. Patients were 65 male HIV-infected patients, 28 with recent weight loss (WL), and 37 who were weight stable (WS); 50/65 patients had AIDS, and 29/65 had acute infections; 29 male healthy persons served as controls. Indirect calorimetry, prospective intake protocol, and bioelectrical impedance analysis were performed. Absolute REE was lower in WL patients than in controls (1459 +/- 309 versus 1711 +/- 151 kcal/d, p < 0.001) and in WS patients (1625 +/- 402 kcal/d, p < 0.05). REE/kg body cell mass (BCM) was higher in WL and WS than in controls (both p < 0.01) due to lower BCM in both patient groups (p < 0.001). REE (%Harris-Benedict) was not different among the three groups. Weight changes around the measurement were not correlated to REE (r2 = 0.0008, p = 0.82). REE was independent of diarrhea, acute infection, fever, or caloric intake. REE had a stronger correlation to body weight and to Harris-Benedict's prediction than to fat-free mass or BCM. REE explains < 1% of weight changes. Many patients can downregulate REE as an adaption to anorexia and/or malabsorption. Higher REE/kg BCM does not signify hypermetabolism at the cellular level but can be explained by the maintenance of energy-consuming visceral tissue within the BCM during BCM loss.

In a prospective study of HIV patients with suspected cytomegalovirus (CMV) disease (n = 144; 140 men, four women; aged 23-69 years, median 38 years; CD4 cells 0-400, median 20/microliters), 242 blood samples were examined for the presence of CMV-pp65 antigen in peripheral blood polymorphonuclear leucocytes by use of monoclonal antibodies and alkaline phosphatase-anti-alkaline phosphatase staining. All patients were thoroughly examined for existing CMV disease at first visit and during follow-up (at least 2 months or until death: 0-24 months, median 14 months). In 43/486 samples of patients with CMV disease, the antigen-test was positive and in 179/194 samples of patients without CMV disease the test was negative, resulting in a sensitivity of 90% and a specificity of 93% for the presence of CMV disease in HIV-infected patients.

The frequency of HLA-DQ antigens in AIDS patients with toxoplasmic encephalitis (TE) were examined. HLA-DQ3 was significantly more frequent in white North American AIDS patients with TE (85.0%) than in the general white population (51.8%; P = .007, corrected P = .028) or randomly selected control AIDS patients who had not developed TE (40.0%; P = .016). In contrast, the frequency of HLA-DQ1 was lower in TE patients than in healthy controls (40.0% vs. 66.5%, P = .027), but this difference did not reach statistical significance when corrected for the number of variables tested (corrected P = .108 for the general white population). HLA-DQ3 thus appears to be a genetic marker of susceptibility to development of TE in AIDS patients, and DQ1 may be a resistance marker. These HLA associations with disease indicate that development of TE in AIDS patients is affected by a gene or genes in the HLA complex and that HLA-DQ typing may help in decisions regarding TE prophylaxis.

Human immunodeficiency virus type 1 (HIV-1) seropositive individuals suffer from a depletion of T4+ T cells and have elevated plasma glutamate levels. Glutamate is also elevated in cancer patients, and several authors have shown that elevated extracellular glutamate levels inhibit competitively the membrane transport of cystine and cause a decrease of intracellular cystine. We, therefore, tested the hypothesis that high glutamate and/or low cystine levels may generally be associated with low lymphocyte reactivity or low T4+ counts. In three independent studies we tested (i) serum amino acid levels (AAL) versus T4+ counts in healthy individuals, (ii) plasma AAL versus lymphocyte responses in healthy individuals, and (iii) plasma AAL versus T4+ counts in HIV-1 seropositive individuals. When the individuals in each study were divided into four subgroups as defined by median glutamate and cystine levels, the results showed that persons with a combination of low glutamate and high cystine level (LGHC subgroups) had the highest mean T4+ count or highest lymphocyte reactivity. Moreover, the LGHC subgroup in a study of lung cancer patients had a much longer mean survival time than the other three subgroups. In HIV-1 infected patients, hyperglutamataemia is associated with hypocystinaemia and hypocysteinaemia. Azidodeoxythymidine (AZT) treated HIV patients had, on average, lower glutamate levels than patients without AZT.(ABSTRACT TRUNCATED AT 250 WORDS)

Sequence data of the small subunit rRNA (SSU-rRNA) gene were used to identify Septata intestinalis in biopsies of human immunodeficiency virus-infected patients by polymerase chain reaction (PCR), southern blot hybridization, cloning, and comparative genetic sequencing. DNA products of correct size could be amplified from all examined tissues with S. intestinalis infection but also from 2 biopsies with Enterocytozoon bieneusi and from 1 biopsy with Encephalitozoon cuniculi infection. Southern blot hybridization with an S. intestinalis-specific probe and partial sequencing of the DNA fragments showed high homology with published S. intestinalis sequences and confirmed that the amplified PCR products really derived from the SSU-rRNA gene of S. intestinalis. PCR testing can detect very light infections with S. intestinalis. Thus, S. intestinalis seems to occur more frequently in the form of latent infections and the true prevalence of the parasites may be much higher than previously reported.

Microsporidiosis is a common finding in HIV-infected patients who have diarrhoea. The species most commonly causing gastrointestinal disease is Enterocytozoon bieneusi. Recently Septata intestinalis has been described as a cause of diarrhoea and disseminated infection in patients with AIDS. A 44-year-old homosexual man with severe immunodeficiency (CD4 cell count 40/microliters) had a history of watery diarrhoea for 2 weeks. Microsporidian spores measuring 1.2 to 1.5 x 2.5 to 3.0 microns were found in stool samples. Electron microscopy of duodenal biopsies confirmed the diagnosis of intestinal microsporidiosis and showed parasitophorous vacuoles with the typical ultrastructure of S. intestinalis. The patient was treated with albendazole (400 mg twice daily) and became asymptomatic within 4 days. No spores could be detected in stool samples after a treatment period of 14 days. About 25 infections with S. intestinalis have been reported to date, and the case presented here is the first in a German patient.

Intestinal microsporidiosis with Enterocytozoon bieneusi was diagnosed in three of 18 HIV-infected patients with chronic diarrhoea. In two cases all known stages of the life cycle of E. bieneusi (merogonial plasmodia, sporogonial plasmodia, sporoblasts, spores) were found in duodenal biopsies by electron microscopical examination, whereas in the third case only merogonial and sporogonial stages were seen. Spores were also visible by light microscopy in semithin sections. Two patients were treated with albendazole (2 x 400 mg/day for 4 weeks) but showed no response. These findings underline the concept of the worldwide distribution of this parasite and verify that it is also frequent in Germany.

Summary Infection with Helicobacter pylori causes chronic active gastritis and has been associated with gastric and duodenal ulcer disease. In biopsy samples of 110 patients with clinical symptoms of active gastritis, H. pylori was detected by means of the polymerase chain reaction (PCR), using species-specific primers defining a 858 by DNA fragment of H. pylori urease βsubunit. Sensitivity and specificity of the PCR was compared with culture, histology and Warthin-Starry stain (WSs), detection of H. pylori urease antibodies in serum and urease testing with the Campylobacter-like organism (CLO) test. PCR yielded specific amplification products in 53 cases, whereas culture of the organisms was positive in a subset of 50 cases. Only direct detection in histological sections of biopsy specimens had a higher sensitivity, with 65 positive samples. In contrast, the CLO test was negative in eleven culture-positive and PCR-positive cases. Significant urease antibody titres were found in 39 patients with histologically confirmed diagnosis. These results placed the sensitivity of PCR between that of the Warthin-Starry stain (WSs) and that of culture. Therefore, PCR can be proposed as a useful rapid and time-saving technique for the detection of H. pylori in gastritis. For epidemiological purposes, fingerprinting with arbitrarily chosen primers by AP-PCR was evaluated. Strain-specific patterns with up to 13 fragments were achieved with 10nucleotide or longer primers (21-nt) with a G+C content ≥ 55%. Thirty-five of 40 strains investigated by this method were distinguishable with a single primer. These results suggest a high level of DNA sequence diversity within this species with the possibility of confirming the clonality in consecutive isolates from a single individual. Alternatively, an increased in-vivo mutation rate could be responsible for DNA divergence, resulting in specific strains for each individual patient.

In a randomized open trial foscarnet 90 mg/kg b.i.d. 5 days for 3 weeks was compared to 90 mg/kg b.i.d. daily in severe gastrointestinal cytomegalovirus disease in HIV-infected patients. Thirty-eight patients were randomized, 36 were evaluable (all male, age 24-54 years, median 40 years; CD4/microliter 0-150, median 10). Treatment efficacy was evaluated based on a score consisting of symptoms, endoscopic and histologic examination. In the 5-day treatment group 10/16 (62%) patients responded to treatment, in the 7-day treatment group 13/20 (65%), with symptoms resolving in most patients after 1 week. Side effects and adverse events were seen in 13 patients in the 5-day treatment group and in 15 patients in the 7-day treatment group. Laboratory abnormalities were common in both groups, in one patient reversible renal insufficiency developed. Efficacy and safety of treatment 5 days a week was comparable to the standard regimen.

Microsporidia are obligate intracellular protozoan parasites that infect a broad range of vertebrates and invertebrates. They are increasingly recognized as human pathogens, especially in patients infected with human immunodeficiency virus (HIV). Organisms of the genus Encephalitozoon have been implicated as a major cause of disseminated microsporidian infections in persons with AIDS. Until recently, E. hellem was the only Encephalitozoon species confirmed by antigenic or nucleic acid methods to have infected humans. We describe the clinical course and morphological features of a case of disseminated microsporidian infection with Encephalitozoon cuniculi in an HIV-infected patient with chronic sinusitis, rhinitis, and keratoconjunctivitis. Parasites were found in conjunctival swab, nasal discharge, sputum, urine, stool, and duodenal biopsy specimens, but no pulmonary, renal, or gastrointestinal symptoms were documented. The patient was treated with albendazole (400 mg po b.i.d.), resulting in complete remission of his ocular and nasal symptoms, and microsporidian spores disappeared from all sites. To our knowledge, this case is only the second of E. cuniculi infection in humans that has been confirmed by either antibody- or nucleic acid-based methods, and it is the first in which an Encephalitozoon species has been found in the intestinal tract of a human. Microsporidiosis is an important emerging opportunistic infection in HIV-infected patients and, as documented in this report, has an expanding clinicopathologic spectrum.

AIMS--To detect intestinal microsporidiosis in paraffin wax embedded biopsy specimens using a fluorescence technique incorporating optical brighteners. METHODS--Eight HIV infected patients with confirmed intestinal microsporidiosis (six with Enterocytozoon bieneusi, one with Encephalitozoon intestinalis and one with Encephalitozoon cuniculi infection) and 10 without infection were studied. Tissue sections of paraffin wax embedded duodenal biopsy specimens were stained with 1% Uvitex 2B, coded and analysed independently by two investigators. RESULTS--In all eight cases with confirmed intestinal microsporidian infection, spores could be detected easily in tissue sections using the fluorescence technique. Spores or other elements consistent with microsporidiosis were not found in the 10 patients without infection. CONCLUSION--Staining of tissue sections from paraffin wax embedded intestinal biopsy specimens with stains incorporating Uvitex 2B is a rapid and easy technique for the diagnosis of intestinal microsporidiosis.

Intestinal microsporidiosis has been implicated as a major cause of chronic diarrhea in human immunodeficiency virus (HIV)-infected patients. So far diagnosis depends on direct visualization of the parasites by light and transmission electron microscopy. We evaluated the diagnostic value of microsporidian DNA amplification by PCR on duodenal biopsy specimens obtained from patients with and without intestinal microsporidiosis caused by Enterocytozoon bieneusi. Thirteen HIV-infected patients (all CDC stage C3) were studied. Eight patients had intestinal microsporidiosis caused by E. bieneusi (n = 6), Septata intestinalis (n = 1), and Encephalitozoon cuniculi (n = 1); microsporidioses were diagnosed by light microscopy of stool samples and confirmed by light and electron microscopy of intestinal biopsy specimens. Five patients had no microsporidia in their stool samples or in their intestinal biopsy specimens, as examined by light and electron microscopy. Additionally, DNA prepared from Toxoplasma gondii derived from mouse ascites was used as a further control. A 353-bp DNA fragment of the small-subunit rRNA gene could be amplified from all six biopsy specimens infected with E. bieneusi, and the nature of the PCR products was confirmed by Southern blot hybridization. No amplification of DNA fragments was seen by using DNA extracted from biopsy specimens with S. intestinalis or E. cuniculi infection or without microsporidian infection and with template DNA extracted from T. gondii. The results suggest that PCR testing of intestinal biopsy specimens may be a useful approach to diagnosing microsporidiosis in HIV-infected patients.

The prevalence of H. pylori associated gastritis seems to be different in HIV positive and HIV negative patients. Therefore a correlation to immunodeficiency can be postulated. The histology of gastritis, status of H. pylori infection and parameters of humoral and cellular immune response were investigated in 41 HIV positive and 47 HIV negative patients, who were subjected to upper endoscopy for the evaluation of gastrointestinal symptoms. In HIV positive patients 37% had active chronic gastritis against 62% of the HIV negative patients. In 73% of HIV positive cases of active chronic gastritis H. pylori was detected by bacteriological culture and/or Warthin-Starry stain. In HIV negative patients active chronic gastritis was always associated to H. pylori infection. Production of antibodies as measured by two commercially available ELISA tests was significant in HIV positive and HIV negative patients; both tests correlated well with H. pylori detection by culture or direct microscopy. Immunoglobulin class specific immunoblots corresponded to the ELISA results in HIV negative patients but to a lesser extent in the HIV positive group which was assumed to be related to unspecific polyclonal activation in these patients. Systemic cellular immunity was investigated by proliferation assays of peripheral blood mononuclear cells (PBMC). Proliferative response to the unspecific mitogen PHA was reduced in HIV positive patients. A sonicated H. pylori antigen failed to induce lymphocyte proliferation. The antimitogenic effect was also seen in case of coincubation with PHA. This observation was independent of H. pylori and HIV infection status. We conclude that in HIV positive as in HIV negative patients active chronic gastritis is predominantly related to H. pylori infection. The prevalence of H. pylori associated gastritis in HIV positive patients is significantly reduced (p < 0.025) compared to HIV negative controls. Decreased susceptibility to H. pylori infection in HIV positive patients may not be explained by the abnormal reactivity of their humoral or cellular immune response.

In this study we describe a method which makes possible the determination of the free amino acids in biopsies of human gastrointestinal mucosa. Biopsies of duodenal or colonic mucosa were obtained from internal patients without histologically proven pathological processes of duodenum or colon during routinely performed gastrointestinal endoscopy. After shock-freezing in fluid nitrogen and lyophilization, the analysis of the extracts was performed by ion exchange chromatography. Standard deviations of the individual amino acid concentrations of 3 parallel specimens was 3–13% (except histidine: 19%). The sum of all amino acids without taurine was 61.9 (5.4) mmol/kg dry weight (mean, SD of 7 patients) in duodenal biopsies, and 82.9 (0.6) in colonic specimen; 50% (44%) of which consisted of aspartate and glutamate, and 14% (12%) of total essential amino acids. The relative amino acid pattern differed completely from the muscle pattern: aspartate was fourfold higher; glutamate, phenylalanine, glycine, valine, leucine, isoleucine about twofold higher. In contrast, glutamine amounted only to 4% (duodenum)/ 14% (colon) of muscle glutamine. The results obtained from duodenum were compared with that of HIV-positive patients (n=3). We found enhanced intracellular levels of serine and glutamate (150% of normal), glutamine (220%), valine (125%), and ornithine (410%). Amino acid analysis of endoscopically obtained mucosa biopsies might be helpful to monitor intestinal amino acid metabolism, as well as the effect of nutrition therapy in critically ill patients.

Homosexual persons or human immunodeficiency virus (HIV)-infected patients frequently excrete cysts of nonpathogenic strains of Entamoeba histolytica ("Entamoeba dispar"). However, invasive amoebiasis is rare. We report two patients with AIDS and cytomegalovirus colitis in whom invasive amoebiasis was histologically diagnosed. It is concluded that E. histolytica has to be considered in HIV-infected patients with colitis.