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Histoplasma capsulatum is an opportunistic dimorphic fungus responsible for most often self-limiting or flu-like infections but potentially lethal in immunocompromised hosts. Histoplasmosis is rare in Europe. We reported a case of disseminated histoplasmosis in an African HIV patient with a leprosy-like primary cutaneous presentation and involvement of lungs, brain, limphnodes and eye. The therapy with liposomial B amphotericin and itraconazole led to a prompt resolution of the symptoms.

It is reported on the ground of the most updated literature evidences an infrequent case of multiple cavitating pulmonary infiltrates and a probable liver abscess caused by a Nocardia asteroides disseminated infection heralding a HIV-related profound immunodeficiency who remained missed and undiagnosed until the emerging of this severe opportunistic infection.

Aim: 1) To identify the principal radiological signs of atypical pulmonary mycobacteriosis by means of X-rays and CT/HRCT; 2) to compare the two methods in order to evaluate their reliability with particular interest for the diagnostic role of HRCT in the identification of the disease; 3) to establish any significant differences in the pathology between AIDS and immunocompetent patients., Material and Methods: The chest X-rays and CT/HRCT of 28 atypical pulmonary mycobacteriosis patients (16 with AIDS and 12 immunocompetent) have been studied. The subjects were examined during the period of October 1993 to May 2000 and were found to be positive for atypical mycobacterium and consequently underwent a standard chest X-ray. Twenty cases were followed-up with a chest CT/HRCT; of these only 17 were performed within 30 days of the traditional chest X-ray which was considered to be the time limit in order to validate the comparison between the two methods., Results: The significant semeiotical findings were the parenchymal consolidations observed in 25 patients (89%) by standard chest X-rays; the CT/HRCT confirmed the findings in 4 cases while in 13 it enhanced the evaluation of their extensions. In 9 cases the standard chest X-ray established the presence of cavitations which were confirmed by the CT/HRCT in only 7 cases. Lymphadenopathy was observed in 3/28 patients (10.7%) through standard X-rays and in 15/17 cases (82%) through CT/HRCT. The latter method revealed to be extremely useful in the identification of this pathology. Nodules and micronodules were seen in 5 patients with traditional X-rays and in 9 cases with CT/HRCT. Bronchogenic spread signs of disease became visible only with CT and in particular with HRCT (11/17 patients = 65%). Comparing the two groups (AIDS and immunocompetent) taken into consideration, the most frequent lesion present in both was parenchymal consolidation resulting more bilateral in the AIDS subjects. Cavitation and pleural edema were seen more often in the AIDS group while bronchiectasia, bronchogenic spread and signs of previous pleuro-parenchymal suffering were more frequent in the immunocompetent patients. Lymphadenopathy was frequently found in the total study population but appeared slightly prevalent for the group not afflicted with AIDS., Conclusion: Radiological study of the chest permitted the identification of signs useful in the diagnosis of mycobacteriosis in all the patients studied. The application of CT/HRCT added helpful elements in almost all of the cases examined demonstrating to be more effective than the standard chest X-ray not only in terms of improved evaluation of known lesions but also in the identification of lesions which are difficult to determine by means of traditional radiology.

In order to assess the clinical role of bacterial complications due to Acinetobacter spp. during HIV disease, a retrospective survey of clinical and microbiological data of 2221 HIV-infected patients hospitalised during the past 10 years was carried out, evaluating all episodes of Acinetobacter spp. infection according to several epidemiological, clinical and therapeutic variables. Eleven patients of 2221 (0.5%) suffered from Acinetobacter spp. disease: sepsis in 5 cases, and urinary, respiratory tract disease and bacteremic pneumonia in three, two, and one patient respectively. A. calcoaceticus was responsible in 4 cases, A. lwoffii in three, and Acinetobacter spp. in the 4 remaining cases; 4 patients experienced a polymicrobial infection, and 7 had a prior diagnosis of full-blown AIDS. All patients had a severe HIV-related immunodeficiency (mean CD4+ lymphocyte count 118.2 +/- 45.3 cells/microl). Compared with other localizations, sepsis was related to a lower mean CD4+ cell count (p<.001), and a more frequent occurrence of leucopenia-neutropenia (p<.005). Disease episodes diagnosed after the first 72 hours of hospitalisation (deemed no- socomial in origin), proved more frequent than community-acquired ones (9 cases versus 2), affected predominantly patients with AIDS and neutropenia, and were frequent1y associated with bacteremia (p<.04) The use of broad spectrum antibiotics, corticosteroids and cotrimoxazole, was recognized during the month preceding the diagnosis of Acinetobacter spp. disease, in 6, 4, and 8 cases, respectively. One patient only had an indwelling intravascular catheter, while no recent history of surgery, intensive care, or other invasive procedures was found. At in vitro susceptibility studies, bacterial isolates showed complete resistance to ampicillin and cephalothin, and low sensitivity to second-generation cephalosporins, while a higher susceptibility rate was revealed towards ceftazidime, netilmicin, amikacin, and quinolones, followed by cotrimoxazole and piperacillin. A prompt and appropriate antimicrobial therapy (mostly carried out with cephalosporins and aminoglycosides), led all patients to a clinical and microbiological cure within 6-1.3 days, in the absence of mortality or relapses. As opportunist pathogens with a predominant nosocomial origin, Acinetobacter spp. organisms may be responsible for an appreciable morbidity in patients with HIV disease, especially when additional risk factors (immunodeficiency, underlying diseases, and hospitalisation) are present. Notwithstanding the high drug resistance profile of the majority of isolated organisms, a timely diagnosis and a treatment based on in vitro assays, contribute to avoid recurrences and potentially life-threatening complications.

Background: The significant frequency of oropharyngeal candidiasis due to C. albicans in HIV-infected and AIDS patients and the undoubted differences in pathogenicity among strains, lead us to study whether a possible correlation exists between the phenotypic characteristics of the fungal strain and the blastospores adhesivity to the human buccal epithelial cells., Methods: From 203 oro-pharyngeal swabs of HIV-infected patients, 133 C. albicans were identified among 159 yeast strains. Analytical strains delineation below the species level was made by the morphotyping method, assigning a morphotype code of three digits, each of which being expressive of one colonial fringe characteristic. To study the possible blastospores adhesivity differences, we have isolated 10 strains of C. albicans, chose according to the more significant colonial morphologies; they were mixed with oral epithelial cells obtained by scraping of 36 HIV-positive patients and 2 volunteer donors HIV-negative at the rate cells/blastospores of 1:20. Suspensions were filtered, fixed and examined by optical microscope (MO) for counting the number of blastospores adhering to 100 epithelial cells and the number of cells with adhering blastospores., Results: The index obtained by comparing the two qualitative analysis was higher for these isolates producing a rough or very coarse lateral fringes., Conclusions: This finding suggests that these strains may possess the highest adhesive properties, in fact the index decreases progressively to reach lower values for the strain not producing fringe.

Background: Oro-pharyngeal candidosis is a frequently initial clinical manifestation of HIV infection and the adhesive properties of Candida spp. represent a very important pathogenicity factor., Methods: In this study the adhesivity rate of Candida albicans to the oral epithelial cells of 33 HIV-positive patients and 12 healthy volunteers, have been assessed before and after the exposure of blastospores to inhibitory concentrations of fluconazole, in relation to 11 morphotypes obtained from 13 C. albicans strains., Results: Results can be summarized as follows: 1) the number of blastospores adhering to the HIV-positive donor' cells is higher than that of blastospores adhering to the healthy donors' cells (rate is 2.7:1); 2) blastospores from strains producing rough or very coarse fringes show adhesive properties higher than those of strains with different morphology; 3) in the group of HIV-positive patients the adhesivity inhibition of blastospores from strains producing rough or very coarse fringes was higher (38.3%) than that of strains with different morphology (33.8%); 4) overall, adhesivity inhibition due to exposure to fluconazole is higher for epithelial cells from healthy donors., Conclusions: These results can suggest the validity of an antimycotic pretreatment of persons at risk of oro-pharyngeal candidiasis.

Diagnostic techniques of AIDS-related cryptococcosis were assessed in a series of 43 HIV-infected patients, and microbiological features were correlated to the clinical course and outcome of disease. Polysaccharide antigen detection was the most sensitive method for central nervous system infection, followed by direct microscopy and culture: in 4 patients this visceral mycosis was initially diagnosed by the detection of isolated cerebrospinal fluid antigen. Thirty-one patients out of 43 suffered from disseminated infection (with positive blood cultures and/or antigenemia). The occurrence of clinical relapses, a lethal outcome, and time to relapses or to death, did not differ significantly between patients with isolated central nervous system and those with disseminated cryptococcosis.

During the last decade, scientific studies and new knowledges concerning HIV infection and AIDS, have constituted one of the main topics for discussion in the fields of biology and medicine. AIDS is a serious disease and it is unfortunately characterized by a very high death rate. In spite of all the efforts deployed by researchers and scientists, there is at present no effective therapy capable of restoring a proper immunological balance in the affected subjects. In the field of odontostomatology all diagnostic, clinical or therapeutic operation in HIV patients, is to be considered as particularly complex and characterized by some degree of real risk. It is therefore necessary to develop a whole set of health-care models which must provide a broad range of different interventions in order to assure a rational and technically profitable service. We point to the various diagnostic, clinical and therapeutic methods and approaches to be recommended in the case of HIV and AIDS patients, and we add some reference to health care activities at the "San Luigi Center" of the Scientific Istitute San Raffaele Hospital in Milan.

Opportunistic infections are, together with some specific neoplasias, the main problem facing the physician when treating patients affected with AIDS. In fact complications arising from infections correlated to the syndrome are a major factor in both morbidity and mortality. In recent years, thanks to improvements in diagnostic techniques, it has become possible to diagnose opportunistic infections much earlier than in the past, and the use of new antiviral and antifungal molecules has provided the means for more effective treatment, with lower toxicity. In the present study we examine the clinical and diagnostic implications of opportunistic mycotic pathologies, in particular candidiasis of the oral mucosa, which occurs frequently in HIV-positive and AIDS patients. In determining the clinical, diagnostic and therapeutic aspects of mycosis of the oral cavity, close collaboration with the pathologist is crucial importance to the stomatologist, as well as objective clinical examination and microbiological culture tests.

We report a case of a HIV+ patient treated with prophylactic aerosolized pentamidine. The patient showed evidence of tensive right pneumothorax and slight pleural effusion. The pleural fluid was aspired from the drainage and processed in our laboratory. The cytologic examination of aspired fluid revealed abundant Pneumocystis carinii organisms. The cytologic presentation is peculiar in pleural fluid because of the presence of a large amount of trophozoites and a small number of cysts. Direct examination and Giemsa stain are suitable methods to detect trophozoites. The diagnosis can be confirmed by Gomori and Toloidine Blu stains that demonstrate the presence of isolated and scarce cysts. Pneumocystis carinii can also be recognized in Papanicolaou-stained smears as eosinophilic aggregates.

The above study was intended to evaluate certain pharmacokinetic properties as well as the pharmacological activity of fluconazole in patients with cryptococcal meningitis. The results obtained show satisfactory bioavailability of the drug in the cerebrospinal fluid and marked reduction of the number of fungi found in the liquor.

The Authors describe a case of dessicant pseudomembranous vaginitis caused by HPV types 6, 11, 16 and 18 in a 44-year-old HIV seropositive woman. A material mixed with blood, simulating a spontaneous abortion because of its quantity and consistency, was ejected vaginally. A spontaneous abortion was excluded on the basis of a pelvic echographic exam and on the beta-HCG plasma level. Histologic examination of the ejected material demonstrated an epithelium of the vaginal mucosa in which was found a marked and extensive koilocytosis of intermedial and parabasal layers. The vaginal mucosa in this patient differed from the commonly observed koilocytosis and condylomatous proliferation histological aspects seen in vaginal HPV lesions. In the context of the epithelium, by means of confluence of voluminous koilocytotic elements, pseudocystic lacunar spaces of varying dimensions definable as "koilocytotic pseudocysts" were observed. Within the vaginal epithelium, along a line of reduced resistance, a massive and extensive dessication resulted in a laminar detachment of the overlying epithelial stratum. Regarding the association between HIV and HPV infection, it is known that seropositive patients with immunodeficiencies are at high risk of infection by a variety of pathogens and, among these, different types of HPV. The viral association in this case undoubtedly promoted the extension and seriousness of the lesion and its exceptional complication.

We report on the occurrence of an uncommon pathogen, Rhodococcus equi (R.e.) in HIV infection. In the period february 1990-July 1991 we performed the diagnosis of R.e. infection (lung, lung-central nervous system) in two infected patients, aged 27 and 31 years, both males, drug addicts, classified as CDC IV. In the first of them an cavitating right bronchopneumonia (bpm) was diagnosed as of tuberculous origin, on the ground of the microscopic demonstration of an acid-fast, gram-positive strain in b.a.l.. A standard antituberculous regimen was uneffective and R.e. was eventually isolated in three blood culture taken shortly before the exitus and at post-mortem examination of the lungs. In the second patient a subclavian right bpm developed without microbiological evidence of any common pathogen. A third-generation cephalosporin course was only partially successful (clinical amelioration, incomplete clearing of radiological findings). After 3 months the patient relapsed and an aseptic meningitis developed. Cultures of blood and csf yielded a R.e. strain; post-mortem examination revealed a diffuse, cavitating bpm. Our personal experience underlines the difficulty in recognizing R.e. infections in compromised host, because of similarity to other entities (i.e. tuberculosis) and the absence of pathognomonic hints.

The authors describe the clinical-radiological aspects of the most frequent lung infections during AIDS and point out the methods actually applied to define the correct etiological diagnosis of these complications. Therapy problems are widely reported at the ending part of the review together with useful parameters for the prognostic evaluation of respiratory infections in AIDS patients.

Main etiologic agents of AIDS-related infections pneumonia and diagnostic tools useful to identify microorganism are discussed. Bronchoalveolar lavage (BAL) remains the most important performed technique to collect pulmonary secretions, but it needs to be completed by colorimetric, immunological (monoclonal antibodies), serological (ELISA vs. mycobacterial antigens), molecular (DNA probes) techniques. These tools are very useful to identify pathogen agents.