[Prevalence of Bartonella spp. seropositivity in human immunodeficiency virus-infected and non infected intravenous drug abusers]

BACKGROUND

Serology is an useful tool in the diagnosis of Bartonella spp. infections in human immunodeficiency virus (HIV) seronegative patients. The value of this technique in HIV co-infected individuals is unknown. The aim of this study was to assess the prevalence of Bartonella spp. seropositivity among intravenous drugs abusers (IDA), both HIV-infected and non-infected.

PATIENTS AND METHOD

A retrospective seroepidemiological study was carried out among 241 IDA. One hundred and forty-seven of them were infected with HIV type 1. The titer of serum IgG antibodies against Bartonella spp. were determined.

RESULTS

Thirty-three (14%) individuals were seropositive for Bartonella spp. Nineteen (13%) seropositive cases were found among HIV carriers and 14 (15%) among HIV uninfected people. No relationship between Bartonella spp. seropositivity and the CD4+ cell counts was found when HIV infected patients were analyzed.

CONCLUSIONS

We have found a similar prevalence of Bartonella spp. seropositivity in HIV-infected and non HIV-infected IDA.

Heat shock protein of Mycoplasma salivarium and Mycoplasma orale strains isolated from HIV-seropositive patients

It has been suggested that infection by some mycoplasma species can act as possible cofactors in the acceleration of immunodeficiency in HIV-infected patients. The present study was designed to examine infections by oral mycoplasma species in HIV-seropositive (HIV(+)) patients. Mycoplasma salivarium and Mycoplasma orale were isolated from 59.5% and 16.7% of 42 HIV(+) patients, respectively. Non-M. salivarium and non-M. orale species were isolated from 40.5% of saliva samples from the HIV(+) group and 20.8% of those from 24 HIV-seronegative (HIV(-)) subjects, respectively. Although the production of superantigen by human peripheral lymphocytes in the isolated mycoplasma species from HIV(+) and HIV(-) subjects was evaluated, none of the examined mycoplasma strains, including ATCC strains of M. salivarium, M. orale, Mycoplasma buccae and Mycoplasma penetrans, were found to produce superantigen. Production of heat shock proteins (HSPs) by isolated mycoplasma strains was examined by immunoblotting using monoclonal antibodies against Helicobacter pylori HSP60. It was found that all the strains of M. salivarium, M. orale, and unidentified mycoplasma species isolated from HIV(+) and HIV(-) groups produced heat shock proteins. HSP production by oral mycoplasma may play a role in the immunomodulation of HIV(+) patients.

Susceptibility of Candida albicans isolates from the oral cavities of HIV-positive patients to histatin-5

STATEMENT OF PROBLEM

Oral surfaces, including the denture-fitting surface, may serve as a reservoir for disseminated candidal infections, particularly in immunocompromised hosts such as patients with AIDS. Histatins are a group of small, cationic antifungal peptides present in human saliva. There is limited information on the antifungal activity of peptides against Candida albicans isolates from HIV-positive patients.

PURPOSE

This study investigated the fungicidal effects of histatin-5 against oral isolates of C. albicans from HIV-positive and HIV-negative patients.

MATERIAL AND METHODS

An isolate of C. albicans from each of 2 HIV-positive patients (both male) and 3 HIV-negative patients (2 male and 1 female) was obtained. American Type Culture Collection 90028 served as a reference strain. All isolates were identified with sugar assimilation tests and the germ tube test. Fungicidal assays were performed on exponential C. albicans cells in the presence or absence of 0.315 to 50 microm of histatin-5. Numerical data were subjected to 1-way analysis of variance and Tukey's multiple range test (P<.05).

RESULTS

Histatin-5 (50 microm) killed more than 95% of C. albicans isolates from HIV-negative patients and more than 90% of isolates from the reference strain. The same treatment induced 75.3% and 66.1% loss of viability in C. albicans isolates taken from HIV-positive patients (A1 and A2 cells, respectively). The difference between the fungicidal effects in the HIV-positive and HIV-negative groups was significant. (P<.05).

CONCLUSION

Within the limited population of this study, C. albicans isolates from the oral cavities of HIV-positive patients were less sensitive to histatin-5 than oral isolates from HIV-negative patients.

Rapid seroconversion to Treponema pallidum and HIV positivity in a patient with retinal vasculitis

A patient with idiopathic retinal vasculitis was found to have rapid conversion of serological tests for Treponema pallidum and HIV. The diagnosis was confirmed by Venereal Disease Research Laboratory (VDRL) testing and dark ground illumination for T. pallidum, and enzyme-linked immunosorbent assay (ELISA) and Western blot assay tests for HIV. Following treatment with intravenous penicillin, the fundus lesions resolved and visual acuity recovered from inaccurate light projection to 6/24 in the right eye and from counting fingers close to face to 2/60 in the left eye. Serological tests for T. pallidum in patients with concurrent HIV infection may be unpredictable. Hence, it is important to repeat these tests even in the early treatment phase of patients with retinal vasculitis who have shown initial seronegativity. This enables earlier diagnosis and initiation of specific treatment.

Ca3 fingerprinting of Candida albicans isolates from human immunodeficiency virus-positive and healthy individuals reveals a new clade in South Africa

To examine the question of strain specificity in oropharyngeal candidiasis associated with human immunodeficiency virus (HIV) infection, oral samples were collected from 1,196 HIV-positive black South Africans visiting three clinics and 249 Candida albicans isolates were selected for DNA fingerprinting with the complex DNA fingerprinting probe Ca3. A total of 66 C. albicans isolates from healthy black South Africans and 46 from healthy white South Africans were also DNA fingerprinted as controls. Using DENDRON software, a cluster analysis was performed and the identified groups were compared to a test set of isolates from the United States in which three genetic groups (I, II, and III) were previously identified by a variety of genetic fingerprinting methods. All of the characterized South African collections (three from HIV-positive black persons, two from healthy black persons, and one from healthy white persons) included group I, II, and III isolates. In addition, all South African collections included a fourth group (group SA) completely absent in the U.S. collection. The proportion of group SA isolates in HIV-positive and healthy black South Africans was 53% in both cases. The proportion in healthy white South Africans was 33%. In a comparison of HIV-positive patients with and without oropharyngeal symptoms of infection, the same proportions of group I, II, III, and SA isolates were obtained, indicating no shift to a particular group on infection. However, by virtue of its predominance as a commensal and in infections, group SA must be considered the most successful in South Africa. Why group SA isolates represent 53 and 33% of colonizing strains in black and white South Africans and are absent in the U.S. collection represents an interesting epidemiological question.

Effect of commercial ethanol propolis extract on the in vitro growth of Candida albicans collected from HIV-seropositive and HIV-seronegative Brazilian patients with oral candidiasis

The present study assessed the susceptibility of Candida albicans strains, collected from HIV-positive patients with oral candidiasis, to a commercial 20% ethanol propolis extract (EPE) and compare it to the inhibitory action of the standardized antifungal agents nystatin (NYS), clotrimazole (CL), econazole (EC), and fluconazole (FL). Twelve C. albicans strains collected from HIV-positive patients with oral candidiasis were tested. The inhibition zones were measured with a pachimeter and the results are reported as means and standard deviation (M +/- SD). Data were analyzed statistically by the non-parametric Kruskal-Wallis test. EPE inhibited all the C. albicans strained tested. No significant difference was observed between the results obtained with NYS and EPE, while significant differences were observed between EPE and other antifungals. The C. albicans strains tested showed resistance to the remaining antifungal agents. The propolis extract used in this study inhibited the in vitro growth of C. albicans collected from HIV-seropositive Brazilian patients, creating/forming inhibition zones like those ones formed by NYS. This fact suggests that commercial EPE could be an alternative medicine in the treatment of candidiasis from HIV-positive patients. However, in vivo studies of the effect of EPE are needed to determine its possible effects on the oral mucosa.

Ocular syphilis

Although the annual incidence of primary and secondary syphilis has dropped to the lowest rate recorded, syphilis remains an important cause of ocular disease. Uveitis is the most common ocular manifestation of syphilis in both HIV-positive and HIV-negative patients, and the diagnosis should prompt an analysis of the cerebrospinal fluid to exclude associated neurosyphilis. Newer modalities such as enzyme immunoassays and genomic amplification using the polymerase chain reaction may prove to be useful techniques to detect Treponema pallidum in intraocular specimens. The preferred treatment for all stages of syphilis remains parenteral penicillin G, although the preparation, dose, route of administration, and duration of therapy are dictated by the stage of disease and various host factors. All patients diagnosed with ocular syphilis should be tested for HIV, because the presence of a primary genital chancre increases the risk of acquiring or transmitting HIV, and because risk factors for the two diseases are similar.

Identification of Candida dubliniensis in a HIV-positive South African population

Candida dubliniensis was identified as a distinctly separate species of the genus Candida in 1995. Since then the yeast has attracted considerable interest due to its prevalence in HIV/AIDS patients and its ability to develop fluconazole resistance in HIV-seropositive individuals. Although C. dubliniensis has been identified in many centres around the world it has not yet been isolated in Africa. The purpose of this study was to identify C. dubliniensis in an HIV-positive population in the Western Cape, South Africa. A cohort of 50 tuberculosis patients co-infected with HIV was selected on admission to the Brooklyn Chest Hospital, Western Cape. The inclusion criteria for patients accepted for the study were: confirmed HIV seroconversion with a diagnosis of tuberculosis obtained from chest X-rays and sputum microscopy. C. dubliniensis was identified in 6 of the 50 patients accepted onto the study. The prevalence of C. dubliniensis in our study population was lower than that reported in similar North American and European studies. These results confirm the presence of C. dubliniensis in the South African HIV/AIDS population and indicate the urgent need for further investigations into the prevalence and pathogenesis of this clinically important species in both adult and paediatric HIV-positive patients.

A systematic review of the effectiveness of antifungal drugs for the prevention and treatment of oropharyngeal candidiasis in HIV-positive patients

OBJECTIVE

A systematic review of randomized clinical trials published between 1966 and April 2000 was undertaken to determine the strength of evidence for the effectiveness of antifungal drugs (nystatin, clotrimazole, amphotericin B, fluconazole, ketoconazole, and itraconazole) to prevent and treat oral candidiasis in human immunodeficiency virus-positive patients.

STUDY DESIGN

An automated database search identified 366 articles. Six met inclusion and exclusion criteria with respect to prophylaxis; 12 met criteria for treatment of oral candidiasis.

RESULTS

The evidence for the prophylactic efficacy of fluconazole is good, although insufficient to draw conclusions about the other antifungals. Evidence for treatment effectiveness is insufficient for amphotericin B but good for nystatin, clotrimazole, fluconazole, ketoconazole, and itraconazole.

CONCLUSION

Suggestions for strengthening the evidence base include the following: use of larger, more well-defined groups; control for immunologic status, viral load, history of oral candidiasis, past exposure to antifungals, baseline oral Candida carriage, drug interactions, and antiretroviral therapy; and consistent use of compliance monitors, fungal speciation, and susceptibility testing.

In vitro susceptibility of 137 Candida sp. isolates from HIV positive patients to several antifungal drugs

Oropharyngeal candidiasis caused by various species of Candida is one of the most common infections in HIV seropositive or AIDS patients. Drug resistance among these yeasts is an increasing problem. We studied the frequency of resistance profile to fluconazole, itraconazole, ketoconazole, amphotericin B and terbinafine of 137 isolates of Candida sp. From HIV positive or AIDS patients with oropharyngeal candidiasis at Instituto de Inmunología, U.C.V. and the Hospital "Jose Ignacio Baldó", Caracas Venezuela, using the well diffusion susceptibility test (Magaldi et al.). We found that nearly 10% of C. albicans isolates were primarily fluconazole resistant, 45% of C. albicans isolates from patients with previous treatment were resistant to fluconazole, of which 93% showed cross-resistance to itraconazole, and even about 30% of C. tropicalis (n = 13) were resistant to fluconazole and/or itraconazole. To this respect, several recent reports have been described antifungal cross-resistance among azoles. Therefore, we consider that C. tropicalis should be added to the growing list of yeast in which antifungal drug resistance is common. This report could be useful for therapeutic aspect in AIDS patients with oral candidiasis.

Isolation and genotyping of black-pigmented anaerobes from periodontal sites of HIV-positive and non-infected subjects in Thailand

BACKGROUND, AIMS

The aims of this study were to investigate the prevalence of periodontitis, the prevalence of black-pigmented anaerobes and the genotypes of Porphyromonas gingivalis and Prevotella intermedia present in HIV-infected and control subjects in a heterosexual Thai population.

METHOD

50 AIDS patients and 50 control subjects were included in the study. Their periodontal condition was examined by assessment of bleeding on probing, attachment loss and probing depth, and presence of erythema around 6 teeth (16, 21, 24, 36, 41, 44). Subgingival plaque was collected from the mesiobuccal sites of these teeth and was cultured anaerobically for black-pigmented bacteria. Species were characterised using biochemical profiles and total protein profiles. Genotyping of each isolate was performed using PCR techniques.

RESULTS

There was little clinical evidence of HIV-associated periodontitis in the HIV-positive subjects and no difference was found in the prevalence or genotype distribution of black-pigmented anaerobes between HIV-infected and control subjects.

CONCLUSIONS

These data suggest lack of severe periodontal destruction due to HIV-infection in Thailand and that these subjects are not colonised by more numerous or characteristic clones of certain putative periodontal pathogens.

Genetic diversity of Pneumocystis carinii in HIV-positive and -negative patients as revealed by PCR-SSCP typing

OBJECTIVE

To describe the epidemiology of severe Pneumocystis carinii pneumonia (PCP) in HIV-infected and non HIV-infected patients.

METHODS

Bronchoalveolar lavage specimens from 212 European patients with PCP were typed using PCR--single strand conformation polymorphism analysis of four genomic regions of P. carinii f. sp. hominis. Demographic and clinical information was obtained from all patients.

RESULTS

Twenty-three per cent of the patients were presumably infected with a single P. c. hominis type. The other patients presented with two (50%) or more (27%) types. Thirty-five genetically stable and ubiquitous P. c. hominis types were found. Their frequency ranged from 0.4% to 10% of all isolates, and up to 15% of those from a given hospital. There was no significant association between the P. c. hominis type or number of co-infecting types per patient and geographical location, year of collection, sex, age, or HIV status. No more than three patients infected with the same type were observed in the same hospital within the same 6 month period, and no epidemiological link between the cases was found.

CONCLUSIONS

The broad diversity of types observed seems to indicate that multiple sources of the pathogen co-exist. There was no evidence that in our study population inter-human transmission played a significant role in the epidemiology of P. carinii.

Genotypic identification of Candida dubliniensis isolated from HIV patients by MLEE

Candida dubliniensis is a novel species only recently described. This emerging pathogen shares some of the phenotypic characteristics specific to C. albicans but is genetically different. In this study we typed four strains of atypical C. albicans isolated in our laboratory and compared them to 41 strains of C. albicans and 11 strains of C. dubliniensis by several phenotypic methods and by multilocus enzyme electrophoresis. Using factorial correspondence analysis, we distinguished C. dubliniensis and the atypical C. albicans strains from all strains of C. albicans. Atypical C. albicans strains were identified as C. dubliniensis.

[Resistance of Mycobacterium tuberculosis in Zaragoza, Spain (1993-1997) and related factors]

BACKGROUND

To know the frequency of resistance of Mycobacterium tuberculosis in a general hospital and the related factors.

PATIENTS AND METHOD

Transversal study of the sensitivity of Mycobacterium tuberculosis in the Hospital Miguel Servet (Zaragoza, Spain) between 1993-1997; the proportions method was used to study the susceptibility. Statistical analysis of conventional tests and significance level at p < 0.05 were performed.

RESULTS

Four hundred and twenty height patients with culture-positive to Mycobacterium tuberculosis were studied; 136 (31.8%) were HIV+, 121 (28.3%) were HIV and in 171 (39.9%) this situation was unknown. In 47 patients (10.9%) the strains isolated were resistant at least to one drug. Primary resistance was 5.9% (22 patients) and acquired resistance was 42.4% (25 patients). Primary resistance in HIV+ patients was 9. 2% and in HIV patients was 7.5%; acquired resistance in HIV+ patients was greater than in HIV patients (51.8% vs 42.8%). When we compared the resistances between both HIV+ and HIV patients we did not find significant differences. Twenty isolates (4.7%) were resistant to more than one drug and 10 (2.3%) were resistant to at least isoniazid and rifampin. The risk factors for acquired resistance were alcohol (odds ratio [OR] = 2.65; 95% CI, 1.24-5.65), drugs users (OR = 2.33; 95% CI, 1.05-5.17), previous episodes of tuberculosis (OR = 109.40; 95% CI, 15.02-796.43) and homeless (OR = 3.75; 95% CI, 1.26-11.17); we did not find significant differences between the different risk factors according to primary resistance.

CONCLUSIONS

On one study, the resistance of M. tuberculosis is similar to other described in Spain. We haven't found significant differences between both seropositive and seronegative patients. The risk factors for acquired resistance were alcoholism, drug users, previous episodes of tuberculosis and homeless.

Higher prevalence of urogenital mycoplasmas in human immunodeficiency virus-positive patients as compared to patients with other sexually transmitted diseases

We determined the prevalence of three emergent urogenital mycoplasma species (M. fermentans, M. penetrans, and M. genitalium) in comparison to the most common species (M. hominis and U. urealyticum). M. genitalium is probably the third most frequent agent of nongonococcal urethritis (NGU) in men. It has been suggested that M. fermentans and M. penetrans play a role in the development of AIDS. We analysed the urine and the urethral swab samples from 106 HIV-1 infected individuals (HIV group) and 110 HIV-negative patients with NGU (STD group) by using PCR and culture methods. M. genitalium was detected in 0.9% of the urine and in 1.9% of the urethral samples from the HIV group, compared to 9.1% found only in urethral swab samples from the STD group. M. fermentans was detected in 5.7% urethral swabs from the HIV group and in 0.9% from the STD group. M. penetrans was detected in 6.6% urine samples from the HIV group. M. hominis and U. urealyticum showed infection rates of 7.5 and 18.9% in the HIV group, and 0.9 and 13.6% in the STD group. Overall there was a higher prevalence of mycoplasmas in the HIV group than in the STD group, but the significance of these results remains unclear.

[Disseminated mucormycosis in AIDS]

Mucormycosis is a rare often fatal opportunistic condition. It mainly occurs in immunocompromised subjects but rarely in AIDS patients. An eighteen-year-old HIV+ man from Zaire died rapidly from disseminated mucormycosis with pulmonary, cardiac, renal, hepatic, splenic and gastric involvement. Fungi were observed in all these organs with a particular vascular trophism. Rhizopus orizae was identified on cultures. Rapid microscopic diagnosis, in the localized stage, could improve the poor prognosis of this infection.

Large artery vasculopathy in HIV-positive patients: another vasculitic enigma

Human immunodeficiency virus (HIV) infection has impacted on all the systems of the body, and the cardiovascular system is no exception, with small to medium-sized vessel vasculitis being most frequently described. We present 16 HIV-positive patients with large vessel disease consisting of either aneurysms (often multiple) or occlusive disease. Nine men and 7 women ranging in age from 18 to 38 years presented with rupture of aneurysm, transient ischemic attacks, hypertension, ischemia to the lower extremity, or a mass at the site of the aneurysm. Eight patients had 1 aneurysm, 2 had 2 lesions, and the remaining 6 cases had from 3 to 7 aneurysms. Arteries affected included the common carotid, abdominal aorta, common iliac, femoral, and popliteal. Three patients had intercurrent infections, but none had any obvious infective vascular lesion. Only 1 patient had a positive TPHA test for syphilis. Microbiologic culture of both blood and thrombus contents was positive for Staphylococcus aureus in 1 case; no other organisms were cultured. The key histological features were within the adventitia: leukocytoclastic vasculitis of the vasa vasora and periadventitial vessels, proliferation of slit-like vascular channels, chronic inflammation, and fibrosis. There was associated medial fibrosis with loss and fragmentation of muscle and elastic tissue. Intimal changes consisted of duplication and fragmentation of the internal elastic lamina with calcification. Atheroma and marked intimal thickening were not evident We believe that the occurrence of this large vessel vasculopathy (mainly aneurysmal) often with multiple lesions in young HIV-positive patients, is characteristic of possible infective or immune complex origin, with leukocytoclastic vasculitis of vasa vasora and periadventitial vessels being pivotal in many cases.

[Susceptibility to fluconazole and itraconazole in isolates of Candida spp. from HIV-positive and HIV-negative patients]

We studied the possible differences in the pattern of susceptibility to fluconazole and itraconazole in 393 isolates of Candida spp. from the oral cavity of HIV-positive patients and 102 isolates from HIV-negative patients with candidemia or candiduria. We used the broth microdilution method according to the NCCLS guidelines. We observed a decrease in the susceptibility to fluconazole in the group of HIV-positive patients in comparison to those who were HIV negative, especially in Candida albicans (MIC(90) 32 mg/l vs. 1 mg/l and Candida glabrata (MIC(90) 64 mg/l vs. 16 mg/l). Furthermore, we did not find any resistant strains in the HIV-negative group. For itraconazole, the MIC(90) was two dilutions greater in the HIV-positive patients, except for C. albicans, which had a much higher MIC(90) (4 mg/l vs. 0.12 mg/.). Therefore, the decrease in the susceptibility of Candida spp. in the HIV-positive patients must be taken into account when establishing a specific antifungal therapy.

[The correlation between the CD4 count in HIV-positive patients and the radiological findings in diseases of the paranasal sinuses]

BACKGROUND AND OBJECTIVE

Sinusitis is a frequent and typical disease in HIV-positive patients. It was the aim of this study to examine retrospectively computed tomograms (CT) and magnetic resonance images (MRI) of such patients for sinusitis.

PATIENTS AND METHODS

CT and MRI of the nasal sinuses were retrospectively analysed in 71 HIV-positive patients.

RESULTS

Sinusitis was diagnosed in 49 of the 71 patients by conventional radiology (38), CT (13) and/or MRI. In patients with sinusitis, contrary to those without it, there was a significant correlation between progression of the HIV infection, as measured by reduction in CD4 count, and an increased number of symptoms (r = -0.297; p < 0.05). The latter also correlated significantly with the frequency of concomitant sinusitis (r = 0.336, p < 0.05). The radiological findings correlated more closely with the CD4 count when tomography was used. The correlation coefficient for the number of patients with concomitant sinus disease rose from r = -0.305 to r = -0.459 and for the degree of severity from r = -0.324 to r = -0.484 (p < 0.05). Severity of sinus disease was clearly more marked among HIV-positive than HIV-negative patients.

CONCLUSION

The severity of sinusitis in HIV-positive patients correlated directly with the level of the CD4 count. In these patients tomographic methods are preferable to conventional radiology.

Genetic identification of Candida species in HIV-positive patients using the polymerase chain reaction and restriction fragment length polymorphism analysis of its DNA

The polymerase chain reaction was used to amplify a targeted region: an internal transcribed spacer region of the ribosomal DNA from 114 Candida isolates and 65 reference strains. Unique product sizes were obtained for Candida glabrata, C. guillermondii and C. inconspicua. Isolates of C. albicans, C. tropicalis, C. dubliniensis and C. krusei could be identified following restriction digestion of the PCR products. The methods proved to be both simple and reproducible and may offer potential advantages over phenotyping methods.

Molecular characterization by PCR-fingerprinting of Candida dubliniensis strains isolated from two HIV-positive patients in Spain

Six Candida dubliniensis isolates were recovered from two HIV-infected individuals in the course of a prospective study of recurrent oral candidosis among HIV-positive patients in Spain. Candida albicans strains as well as non-albicans strains were also obtained from these two patients. C. dubliniensis strains were germ-tube-positive and produced abundant chlamydospores. Fingerprinting the genomic DNAs of these six C. dubliniensis with the C. albicans-specific probe 27A as well as karyotyping was performed to confirm the identification of these isolates. Further analysis of their genomic DNAs was performed by PCR-fingerprinting with the core sequence of phage M13, and they exhibited species-specific multilocus band patterns, clearly distinct from those of C. albicans isolates analyzed in this study and in a previous one (Diaz-Guerra 1997). Intraspecies variation was also seen among PCR patterns yielded by C. dubliniensis isolates from different patients. Although few strains have been analyzed, the use of this PCR-fingerprinting procedure is a promising tool for further epidemiologic studies with C. dubliniensis. The isolation of C. dubliniensis from Spanish HIV-infected patients contributes to the idea of widespread geographic distribution of this species.

Immunogenicity of three Haemophilus influenzae type b protein conjugate vaccines in HIV seropositive adults and analysis of predictors of vaccine response

HIV-seropositive adults may be at increased risk of infection due to Haemophilus influenzae type b (Hib) as compared with HIV-seronegative adults. Protein conjugate vaccines have been demonstrated to induce protective levels of antibodies against Hib in immunocompetent infants and also in HIV-seropositive infants. In this study we determined the immunogenicity of three protein conjugate Hib vaccines (PRP-D, HbOC, HbNOMP) in 135 HIV-seropositive adults who received one dose of Hib vaccine. Anti-polyribosylribitol phosphate (PRP) antibodies were measured at 0, 1, 3 and 12 months postimmunization by the Farr method. We demonstrate that all three vaccines are highly immunogenic and result in protective (> 1.0 microg/ml) levels of antibody. Overall the anti-PRP antibody level was > 1.0 microg/ml in 26% of patients preimmunization, 91% at both 1 and 3 months, and 79% at 12 months postvaccination. Comparison of responses to the three vaccines over time demonstrated differences in the mean geometric anti-PRP antibody level at 1 month (p=0.03) and the 12 month time points (p=0.03) with lower geometric mean levels in the HbNOMP group, though baseline differences in groups limit the interpretation of these findings. In a univariate analysis of baseline characteristics which predicted poor vaccine response, low total IgG2 levels preimmunization predicted a poor antibody response at 1 month (p < 0.01) and at 12 months (p=0.05), while low CD4 T-cell count predicted poor response at 12 months (p < 0.01). We conclude that all three US licensed protein conjugate Hib vaccines are immunogenic in HIV-seropositive adults, and that baseline CD4 T-cell count and IgG2 levels predict the likelihood of antibody response to vaccine.

Bacteremic pneumococcal pneumonia in HIV-seropositive and HIV-seronegative adults

STUDY OBJECTIVES

To compare the demographic, clinical, laboratory, and microbiological data, and the hospital course and outcome of HIV-seropositive and HIV-seronegative adults with bacteremic pneumococcal pneumonia.

DESIGN

Retrospective observation study conducted over a 2-year period.

SETTING

Academic teaching hospital attached to the University of the Witwatersrand, Johannesburg, South Africa.

PATIENTS

Consecutive patients with bacteremic pneumococcal pneumonia were identified on the basis of positive blood culture results.

INTERVENTIONS

All available demographic, clinical, routine laboratory, radiographic, and microbiological data were recorded retrospectively for each of the patients, and the combined data for the HIV-seropositive patients were compared with those of the HIV-seronegative patients.

MEASUREMENT AND RESULTS

A total of 112 patients (31 HIV-seropositive and 81 HIV-seronegative patients) were entered into the study. The HIV-seropositive patients were significantly younger than the HIV-seronegative patients (32.8 vs 39.6 years old) and had lower admission hemoglobin (11.8 vs 13.4 g/dL), WBC count (10.3 vs 14.3 x 10(9)/L), serum albumin (31 vs 36 g/L), sodium (129 vs 132 mmol/L), and potassium (3.0 vs 3.5 mmol/L), respectively. Although the HIV-seropositive patients appeared to have more multilobar pulmonary consolidation on the chest radiograph than the HIV-seronegative patients (60% vs 34%), this did not quite reach statistical significance. In addition, the HIV-seropositive patients had significantly more infections (48.4% vs 20.8%) with pneumococcal serogroups/serotypes (serogroups 6, 19, 23, and serotype 14) that are found more commonly in children, and they also had more penicillin-resistant isolates (13% vs 2.5%) than the HIV-seronegative patients, respectively. Similarly, it was noted that when these data were analyzed according to gender (irrespective of HIV status), women had significantly more infections than men (47% vs 21%) with serogroups/serotypes that are usually found in children, more penicillin-resistant isolates (15% vs 1%), and more co-trimoxazole-resistant isolates (21% vs 5%), respectively. There were no differences noted in any of the other parameters, including initial APACHE (acute physiology and chronic health evaluation) II score, PaO2/fraction of inspired oxygen ratio, duration of temperature, duration of IV therapy, duration of hospitalization, complications, and outcome, when comparing HIV-seropositive and HIV-seronegative patients. Two patients in each group died.

CONCLUSIONS

The clinical features of bacteremic pneumococcal pneumonia are similar in HIV-seropositive and HIV-seronegative patients. Although differences are noted in various laboratory and microbiological parameters, they do not appear to have an impact on outcome.

[Genotype, serotype and sensitivity to fluconazole of Candida albicans strains isolated from HIV-positive patients]

Genotype, serotype and susceptibility in vitro to fluconazole of 104 C. albicans strains isolated from HIV+ patients were studied. The possible correlations between genotype analysed by multilocus enzyme electrophoresis (MLEE) and phenotype of medical relevance (serotype and susceptibility to fluconazole) of Candida albicans isolated from these patients treated with fluconazole were evaluated by factorial correspondence analysis. No correlation was observed between genotype and in vitro or clinical response to fluconazole. In counterpart, serotype B C. albicans was associated with some multilocus genotypic patterns.

Serotype distribution and secretory acid proteinase activity of Candida albicans isolated from the oral mucosa of patients with denture stomatitis

Denture stomatitis is the most common form of oral Candida infection in humans. In the current study, the distribution of Candida albicans serotype A and B as well as the activity of the secreted acid proteinase were determined in clinical isolates from patients with denture stomatitis. It was found that 70% of individuals with clinical signs of denture stomatitis exhibited fungal growth, with C. albicans representing the most frequently isolated species (75%). Of the C. albicans isolates, 75% were serotype A and 25% were serotype B, representing a significant increase of serotype B compared to a control group of non-denture-wearing HIV-seronegative individuals with oral candidiasis, but no significant difference compared with isolates from HIV-seropositive patients, who also exhibited a high percentage of serotype B. The mean secretory acid proteinase activity of C. albicans isolates from denture stomatitis patients (2796 +/- 819 U/l) was statistically not different from the mean secretory acid proteinase activity in non-denture-wearing HIV-seronegative individuals (2324 +/- 1487 U/l). Both values were significantly lower than the mean secretory acid proteinase activity of C. albicans from HIV-seropositive individuals (4256 +/- 2372 U/l). No correlation exists between the C. albicans serotype and the amount of secreted acid proteinase, indicating that serotype and secretory acid proteinase expression are two independent pathogenetic factors in oral candidiasis. These results indicate that there seems to be strain selection for C. albicans serotype B in denture stomatitis. These results further indicate that increased secretion of the acid proteinase seems to be of pathogenetic significance in the candidiasis of HIV-seropositive patients but not in denture stomatitis. Nevertheless, the secretory acid proteinase is likely to be an important pathogenetic factor also in denture stomatitis, where an increased secretion of the acid proteinase may not be required because of decreased salivary flow and a low pH under the denture, which will result in a high enzymatic activity.

Spindle cell tumors associated with mycobacteria in lymph nodes of HIV-positive patients: 'Kaposi sarcoma with mycobacteria' and 'mycobacterial pseudotumor'

Patients infected with HIV often have unusual manifestations of common infections and neoplasms. One such example is "mycobacterial pseudotumor," an exuberant spindle cell lesion induced in lymph nodes by mycobacteria. Kaposi sarcoma also produces a spindle cell proliferation in lymph nodes of HIV-positive patients. These two entities must be differentiated from one another because of differences in treatment and prognosis. We report here, however, three cases of intranodal Kaposi sarcoma with simultaneous mycobacterial infection, the occurrence of which has not been clearly documented. For comparison, we also studied three cases of mycobacterial pseudotumor, of which 14 cases have been described to date. There was considerable histologic overlap between these two lesions. Acid-fast bacilli were present in all cases, predominantly in the more epithelioid histiocytes in the cases of Kaposi sarcoma, and in spindle and epithelioid cells in the cases of mycobacterial pseudotumor. The morphologic features that favored Kaposi sarcoma over mycobacterial pseudotumor were the prominent fascicular arrangement of spindle cells and slitlike spaces, the lack of granular, acidophilic cytoplasm, and the presence of mitoses. Immunohistochemistry was a reliable adjunct study in the differential diagnosis, as the spindle cells in mycobacterial pseudotumor were positive for S-100 protein and CD68 whereas those of Kaposi sarcoma were CD31- and CD34-positive but negative for S-100 protein and CD68. Awareness that Kaposi sarcoma may coexist with mycobacterial infection in the same biopsy specimen is important because these lesions may be misdiagnosed as mycobacterial pseudotumor. The clinical impact of distinguishing between Kaposi sarcoma with mycobacteria and mycobacterial pseudotumor is significant because the presence of Kaposi sarcoma alters treatment and prognosis.

Mycoplasma penetrans and other mycoplasmas in urine of human immunodeficiency virus-positive children

Urine samples from children with human immunodeficiency virus (HIV) infection and healthy controls were examined for mycoplasmas by culture. Standard biochemical assays, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and PCR (16S and 16S-23S spacer rRNA region) were used for identification of isolates. Mycoplasmas were identified from 13 (87%) of 15 HIV-positive patients and 3 (20%) of 15 HIV-negative control patients. The frequency and type of mycoplasma varied with the severity of HIV infection. Mycoplasma penetrans, Mycoplasma pirum, Mycoplasma fermentans, and Mycoplasma genitalium were isolated from patients with severe immunodeficiency. Mycoplasma hominis and Ureaplasma urealyticum were isolated more frequently from children in the early stages of HIV infection and from HIV-negative patients. Mycoplasma penetrans was isolated from one (50%) of two patients in Centers for Disease Control and Prevention (CDC) group B and from five (55.5%) of nine pediatric patients with AIDS (CDC group C). This is the first report that indicates that "AIDS-associated" mycoplasmas are more common in HIV-infected children than in HIV-negative controls.

Non-albicans oral candidosis in HIV-positive patients

Specimens from HIV-positive patients with oral candidosis were taken for culture, species identification and azole susceptibility testing, which was correlated with treatment outcome. Of 921 specimens, 95 yielded non-albicans species, mainly from patients with low CD4 lymphocyte counts and extensive previous azole exposure. Most non-albicans isolates were from specimens co-infected with Candida albicans, complicating the interpretation of in-vitro susceptibility results, which accurately predicted antifungal failure when the non-albicans species was isolated alone. Eighty-five non-albicans isolates were resistant to fluconazole in vitro. Of 149 courses of azole therapy prescribed, 115 failed to clear non-albicans candidosis clinically. Culture media that discoloured in the presence of non-albicans colonies might, therefore, guide therapy.

[Primary resistance of Mycobacterium tuberculosis in 10 hospitals of the community of Castille and Leon. Group of Microbiologists from Castille and Leon]

OBJECTIVE

To determine the primary drug resistance (PDR) of Mycobacterium tuberculosis in ten hospitals in the Castile-León Community for a five-year period (1991-1995), in a sanitary area with almost two millions of inhabitants.

MATERIAL AND METHODS

The sensitivity of 825 strains of Mycobacterium tuberculosis to antituberculous drugs was studied using the proportion method; 773 strains were from HIV-negative patients and 52 from HIV-positive patients.

RESULTS

Thirty-four out of the 824 strains were resistant to one or more drugs: 31 (4%) from HIV-negative patients and 3 (5.7%) from HIV-positive patients. The resistance to the different drugs for strains from HIV-negative patients was: streptomycin, 2.4%; isoniazid, 1.8%; ethambutol, 0.6%, and rifampin, 0.2%. For HIV-positive patients, resistance to streptomycin was 5.7% and to isoniazid 1.9%. Resistance to a single agent was the resistance mode observed most commonly: 23 (2.9%) in HIV-negative patients and 2 (3.3%) in HIV-positive patients. There was not a single strain resistant to isoniazid and rifampin.

CONCLUSIONS

The incidence of PR in the surveyed area was low, including isoniazid. The group of HIV-positive patients did not show a significant increase in resistance (p = 0.4; OR, 1.44; 95% CI, 0.43-4.86). Regular surveillance of drug resistance is recommended to adjust therapeutic regimes.

Identification of Candida dubliniensis in a prospective study of patients in the United States

Although Candida albicans remains the fungal species most frequently isolated as an opportunistic oral pathogen, other yeast species are often identified in human immunodeficiency virus (HIV)-seropositive patients. Candida dubliniensis phenotypically resembles C. albicans in many respects, yet it can be identified and differentiated as a unique Candida species by its phenotypic and genetic profiles. The purpose of the present study was to prospectively test for the presence of C. dubliniensis among clinical isolates and to determine the clinical and demographic characteristics of patients harboring C. dubliniensis. Over a 90-day period, isolates from 724 patients that were presumptively identified as C. albicans were screened for C. dubliniensis by use of tests for germ tube and chlamydospore production, by detection of an inability to grow at 45 degrees C, by colony color on CHROMagar Candida medium, and by the results of a sugar assimilation test with the API 20C AUX yeast identification system. Among 699 isolates retrieved from those specimens evaluated, 5 from 25 HIV-seropositive patients and 1 isolate from a patient whose HIV status was unknown were shown to be consistent by phenotyping and by electrophoretic karyotyping with the European reference strain of C. dubliniensis. One of the C. dubliniensis isolates had dose-dependent susceptibility to fluconazole (MIC, 16 microg/ml). These results confirm the presence of this interesting species in the United States and support the need for further investigations into the prevalence and pathogenesis of C. dubliniensis.

Infectious complications of 393 peripherally implantable venous access devices in HIV-positive and HIV-negative patients

PURPOSE

To compare and investigate the rate of infection in patients with and without human immunodeficiency virus (HIV) who have implantable venous access devices placed by interventional radiologists.

MATERIALS AND METHODS

Three hundred ninety-one patients undergoing radiologically guided placement of peripheral arm ports were grouped according to their HIV serologic status. Findings were prospectively reviewed in 393 peripherally placed arm ports that were implanted in the basilic, cephalic, or brachial vein under fluoroscopic or sonographic guidance over a 4-year span. Infectious complications were categorized according to severity (local or systemic) and time (periprocedural or late).

RESULTS

Three hundred ninety-three ports have been indwelling for a total of 97,256 patient days (range, 1-694; mean duration, 247 days). Among the 30 catheter placements in 29 HIV-positive patients with a total exposure time of 7,242 days, five (one local and four systemic) infections occurred, resulting in a 16.6% overall infection rate, yielding 0.069 infections per 100 catheter days at risk (95% confidence interval [CI], 0.032-0.127). In the remaining 362 HIV-negative patients, 27 (14 local and 13 systemic) infectious complications (7.4%) occurred, translating into 0.030 infections per 100 catheter days (95% CI, 0.021-0.042). The odds ratio of getting an infection from the implantable arm ports in the HIV-positive group was 2.5 times higher than that of the HIV-negative group. The relative risk was similar and was calculated to be 2.3. The P value was .084 (P < .05 required to be considered significant).

CONCLUSIONS

These results suggest a significant difference in the infectious complication rate encountered in HIV-positive patients compared with the general population. However, the HIV-positive peripheral arm port infection rate compares favorably with the surgically placed catheters and ports. Many more arm ports in HIV-positive patients must be evaluated for the data to achieve an acceptable level of statistical significance.

Safety and tolerance of Lactobacillus reuteri supplementation to a population infected with the human immunodeficiency virus

Probiotic supplementation may provide health benefits, especially for individuals with an underlying disease state that makes them more susceptible to infections. The purpose of this experiment was to evaluate the safety and tolerance of Lactobacillus reuteri ingestion by subjects infected with the human immunodeficiency virus (HIV). Thirty-nine subjects consumed a freeze-dried preparation of L. reuteri or a placebo for 21 days in a double-masked, parallel design experiment. Serum chemistry, haematology, immune profile, urinalysis, physical examination, gastrointestinal tolerance and faecal microbiota data were collected. No clinically significant changes were noted in any of the safety parameters measured. Overall, tolerance was good in both groups. Consumption of L. reuteri tended to increase faecal levels of L. reuteri on days 7, 14 and 21 of treatment feeding (P < 0.06, P < 0.11 and P = 0.05, respectively). However, faecal levels of L. reuteri and total Lactobacillus species were lower than levels previously observed in healthy male adults. Overall, this study documents that L. reuteri may be fed to HIV-positive individuals at 1 x 10(10) colony forming units/day without any clinically significant safety or tolerance problems.

An outbreak of methicillin-resistant Staphylococcus aureus (MRSA) infection in HIV-seropositive persons

Staphylococcus aureus is a cause of considerable morbidity and mortality in HIV-seropositive persons. Although methicillin-resistant S. aureus (MRSA) is encountered worldwide and in many areas of medical care, little has been reported on clinical infection with MRSA in patients with HIV. We report on an outbreak of MRSA infection in HIV antibody positive patients, using case reports to describe an outbreak of MRSA infection in HIV-seropositive persons. Six cases of clinical MRSA infection were reported over a 4-week period on patients on an HIV dedicated ward. All cases had previous AIDS diagnoses and low CD4 cell counts (median 8 x 10(6)/l; range 0 to 238). Two cases had infected skin lesions and 2 cases had infected indwelling central venous catheters with septicaemia. Two cases had pneumonia, one with concurrent infection at the entry site of a percutaneous endoscopic gastrostomy (PEG) feeding tube. Isolates of MRSA from the 6 cases were compared by pulsed-field gel electrophoresis of Sma1 chromosomal digests. The resultant banding pattern showed the same strain was responsible for all the infections. A seventh inpatient, the index case, had positive carriage with the same strain of MRSA. To define ongoing MRSA carriage after the outbreak, 29 consecutive ward patients were swabbed for MRSA: all were negative. All patients identified with MRSA infection responded to treatment with intravenous teicoplanin, although carriage was unaltered. Four of the 6 cases died within 7 weeks of diagnosis of MRSA. MRSA can cause severe morbidity in patients with end-stage HIV disease. A small outbreak of MRSA was controlled by simple precautionary measures with no subsequent ongoing transmission of MRSA.

The effect of limited exposure to antimycotics on the relative cell-surface hydrophobicity and the adhesion of oral Candida albicans to buccal epithelial cells

Candida albicans is the major aetiological agent of oral candidosis. Adhesion to oral mucosal surfaces is considered a prerequisite for its successful colonization and subsequent infection, and its relative cell-surface hydrophobicity (CSH) is a contributory physical force. Thus, the main aim here was to determine the CSH of 10 isolates of oral C. albicans after a short exposure to sublethal concentrations of four antifungal agents and to correlate these findings with their adhesion to human buccal epithelial cells (BEC). The yeasts were exposed to sublethal concentrations of nystatin [x 6 minimal inhibitory concentration (MIC)], 5-fluorocytosine (x 8 MIC), ketoconazole (x 4 MIC) and fluconazole (x 4 MIC) for 1 h. The drug was then removed, and the CSH and BEC adhesion assessed by a biphasic aqueous-hydrocarbon assay and a microscopic method, respectively. The mean percentage reductions of CSH after exposure to nystatin, 5-fluorocytosine, ketoconazole and fluconazole were 27.14% (p = 0.01), 9.46% (p = 0.43), 19.47% (p = 0.04) and 6.16% (p = 0.59). Similarly, exposure to all the drugs except 5-fluorocytosine resulted in a significant inhibition of yeast adhesion to BEC, with nystatin eliciting the highest and fluconazole the least inhibition. Further, on regression analysis a strong positive correlation was observed between CSH and adhesion to BEC after limited exposure to 5-fluorocytosine (r = 0.48, p < 0.0001), ketoconazole (r = 0.48, p < 0.0001), fluconazole (r = 0.55, p < 0.0001) as well as in the unexposed controls (r = 0.41, p = 0.001), although nystatin was an exception (r = 0.09, p = 0.44). Taken together, these data elucidate further mechanisms by which antimycotics may operate in vivo to suppress candidal pathogenicity.

Incidence and clinical implications of isolation of Mycobacterium kansasii: results of a 5-year, population-based study

BACKGROUND

Mycobacterium kansasii, an unusual pathogen in the pre-AIDS era, is increasingly reported to cause infection among patients with HIV infection. Little is known about the epidemiology and clinical implications of M. kansasii infection in the AIDS era.

OBJECTIVE

To compare the incidence, demographic characteristics, and clinical features of M. kansasii infection in HIV-positive and HIV-negative persons.

DESIGN

Population-based laboratory surveillance.

SETTING

Three counties in northern California.

PATIENTS

All persons who had a positive culture for M. kansasii between 1 January 1992 and 31 December 1996.

MEASUREMENTS

Cumulative incidence rates were calculated for each year by dividing the number of adult patients by the annual estimated adult population. Demographic and socioeconomic data for a single county were obtained by linkage with the 1990 U.S. Census report.

RESULTS

270 patients (69.3% of whom were HIV positive) were identified, for an incidence of 2.4 cases per 100,000 adults per year (95% CI, 2.1 to 2.7), 115 cases per 100,000 HIV-positive persons per year (CI, 99 to 133), and 647 cases per 100,000 persons with AIDS per year (CI, 554 to 751). Indicators of lower socioeconomic status were common among patients: Median incomes were $32,317 in census tracts in which cases were identified and $38,048 in census tracts without cases (P = 0.001), and 35.7% of patients had unstable housing situations. Ninety-four percent of cases were from respiratory isolates, and 87.5% of patients had evidence of infection. Persons with HIV infection differed from those without HIV infection with respect to mycobacteremia (9.6% compared with 0%; P = 0.001), need for hospitalization (77.4% compared with 51.9%; P < 0.001), and smear positivity (41.7% compared with 20.7%; P = 0.005). Chronic diseases were common among HIV-negative persons; however, 40.3% had no predisposing medical condition.

CONCLUSIONS

Mycobacterium kansasii isolation is more common in HIV-positive persons, but most patients with M. kansasii infection have clinical and radiologic evidence of infection regardless of HIV status. Persons infected with HIV and M. kansasii have a higher rate of hospitalization and a greater burden of organisms. A possible association with poverty suggests mechanisms of transmission and requires further study.

Characterization of Candida albicans isolates from the oral cavity of HIV-positive patients

Characterization of Candida albicans isolates from the oral cavity of Ethiopian Human Immunodeficiency Virus (HIV)-positive patients and HIV-negative individuals was undertaken. After identification of isolates using conventional methods and determination of carbohydrate assimilation profiles, serotyping was performed by slide agglutination with the Iatron IF6 serotyping system. Sensitivity of the isolates to 5-Fluorocytosine (5-FC) was assessed using the broth macrodilution method. There was no difference in phenotype, by any of the three methods used, between the HIV-positive and HIV-negative individuals. Serotype A was found to be dominant in strains isolated from both HIV-positive (34/40 = 85%) and HIV-negative (17/20 = 85%) study subjects. These data suggest that the C. albicans strains causing oral candidiasis in patients with HIV infection are identical to the commensal ones found in healthy individuals.

Passive particle agglutination test for screening of Treponema Pallidum antibodies in blood bank routine

In most laboratories and blood banks, the TP.PA test has replaced the TPHA test for the screening of Treponema pallidum antibodies. In this study we show that the 1:20 serum dilution should be used to discriminate between negative and positive samples instead of the recommended 1:40 dilution, thus increasing sensitivity without a significant loss of specificity.

Detection of specific antibodies to an antigenic mannoprotein for diagnosis of Penicillium marneffei penicilliosis

The disseminated and progressive fungal disease Penicillium marneffei penicilliosis is one of the most common infectious diseases in AIDS patients in Southeast Asia. To diagnose systemic penicilliosis, we developed an enzyme-linked immunosorbent assay (ELISA)-based antibody test with Mp1p, a purified recombinant antigenic mannoprotein of P. marneffei. Evaluation of the test with guinea pig sera against P. marneffei and other pathogenic fungi indicated that this assay was specific for P. marneffei. Clinical evaluation revealed that high levels of specific antibody were detected in two immunocompetent penicilliosis patients. Furthermore, approximately 80% (14 of 17) of the documented penicilliosis patients with human immunodeficiency virus tested positive for the specific antibody. No false-positive results were found for serum samples from 90 healthy blood donors, 20 patients with typhoid fever, and 55 patients with tuberculosis, indicating a high specificity of the test. Thus, this ELISA-based test for the detection of anti-Mp1p antibody can be of significant value as a diagnostic for penicilliosis.

Reduced binding and phagocytosis of Pneumocystis carinii by alveolar macrophages from persons infected with HIV-1 correlates with mannose receptor downregulation

The macrophage mannose receptor, a pattern recognition molecule and component of innate immunity, mediates binding and phagocytosis of Pneumocystis carinii and likely represents an important clearance mechanism in the lungs of immunocompetent hosts. The purpose of this study was to examine the ability of alveolar macrophages from HIV-infected individuals to bind and phagocytose P. carinii, and to investigate the role of the macrophage mannose receptor in mediating this interaction. Compared with healthy individuals, alveolar macrophage phagocytosis of P. carinii from HIV+ persons was reduced up to 74% (P = 0.02), primarily reflecting a reduction in the number of organisms associated with each macrophage (P = 0.019). Furthermore, macrophages from HIV+ individuals demonstrated up to an 80% (P < 0.05) reduction in mannose receptor surface expression and endocytosis. Mannose receptor affinity was unaltered, and mRNA levels were modestly reduced (P < 0.05). Cells from HIV+ individuals with CD4(+) counts < 200 cells/mm3 (representing individuals at high clinical risk for P. carinii pneumonia) demonstrated the lowest levels of P. carinii phagocytosis and mannose receptor endocytosis. In vitro HIV infection of alveolar macrophages from healthy individuals reduced mannose receptor endocytosis to 53.2% (P < 0.05) and P. carinii binding and phagocytosis to 67.4% (P < 0.05) of control. Our studies suggest that HIV infection may alter innate immunity in the lungs, and that impaired alveolar macrophage mannose receptor-mediated binding and phagocytosis of P. carinii may contribute to the susceptibility of HIV-infected individuals to this opportunistic pulmonary pathogen.

[Candida albicans: the relationship between morphotypes and in-vitro adhesivity to the oral mucosa cells of HIV-positive and AIDS patients. I]

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.

[Candida albicans morphotypes and in vitro adhesivity to cells of the human oral mucosa in HIV-positive and AIDS patients after exposure of blastospores to fluconazole. II]

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.

Pathologic outcome in HIV-seropositive individuals with nonspecific bronchoalveolar lavage cytology

OBJECTIVE

To determine the pathologic outcome in human immunodeficiency virus (HIV)-seropositive individuals with nonspecific bronchoalveolar lavage (BAL) cytology.

STUDY DESIGN

The study group consisted of 126 cytologically negative or nonspecific BAL specimens from HIV-seropositive adults. Concurrent microbial cultures and transbronchial biopsies, as well as subsequent pulmonary cytology, lung biopsy or autopsy results were reviewed. Additionally, the cytologic morphology of specimens from patients found to have a potential bacterial pathogen was reviewed.

RESULTS

In the 126 cases with nonspecific BAL cytology, a potential pulmonary pathogen was identified from a concurrent or subsequent pathologic specimen in 27% of cases, while no pathogen was identified in 73% of cases. Bacteria and fungi were the most common pathogens identified. Microbial cultures alone identified the pathogen in 59% of cases, while transbronchial biopsy added information in only 9%. Specimens with marked acute inflammation often yielded bacterial pathogens on microbial culture.

CONCLUSION

A potential pulmonary pathogen can be identified in 27% of HIV-seropositive individuals with negative BAL cytology using other diagnostic modalities. Bacterial pathogens are most common and are usually identified by microbial culture. Marked acute inflammation in a BAL specimen is often associated with bacterial pneumonia.

Role of dentinal carious lesions in the pathogenesis of oral candidiasis in HIV infection

The authors describe a clinicopathologic study that evaluated whether dentinal carious lesions are colonized by candidal organisms--and if so, whether there is a relationship between dentinal carious lesion colonization and clinical oral candidiasis, or OC, in HIV infection. Using light microscopy, the authors examined 30 extracted teeth with dentinal carious lesions from people in each of two groups: 30 consecutively treated HIV-positive patients and 30 consecutively treated HIV-negative patients. OC was diagnosed only in HIV-positive patients (40 percent). The dentinal carious lesion pattern in both groups was similar in occlusal, root and proximal caries. Candidal colonization of carious dentinal tubules was more frequent in HIV-positive subjects than it was in HIV-negative subjects. This research shows that it may be important to restore dentinal caries in HIV-infected patients to remove a protected niche for candidal organisms.

Quantitative cultures of Candida from mouthwash fluid in HIV-infected patients: a longitudinal study

The density of Candida colonization in mouthwash fluid of 59 HIV-seropositive patients and 21 controls was determined. No significant difference in colony-forming units was found. No correlation was found between the colonizing density of Candida albicans and the CD4 count among the patients. Twenty-seven of the HIV-seropositive patients were followed for almost 3 years. No difference was found between the number of Candida albicans colony-forming units at the first and second time of sampling. Vaccination with HIV IIIB GP 160 vaccine did not have any influence on the prevalence of Candida albicans.

Nasopharyngeal flora in HIV seropositive men who have sex with men

OBJECTIVES

To assess, in men who were infected with the human immunodeficiency virus (HIV) and who identified themselves as having had sex with men; the nasopharyngeal prevalence of Neisseria gonorrhoeae, N meningitidis, Corynebacterium diphtheriae, and candida species; oral sexual behaviour; the relation between oral flora and oral sexual behavior.

METHOD

Nasopharyngeal swabs were taken from HIV seropositive men for culture. The men were also asked to complete a self administered questionnaire.

RESULTS

390 men were recruited; 286 (73.3%) provided nasopharyngeal samples and questionnaires; 41 (10.5%) provided nasopharyngeal samples only; 63 (16.2%) provided questionnaires only. From the 327 nasopharyngeal samples N meningitidis was cultured in 49 (15%) and candida species in 165 (50.5%). Cultures for N gonorrhoeae and C diphtheriae were all negative. Data from the 349 completed questionnaires indicated that 285 men were practising oro-penile sex, over 90% did not consistently use condoms; 150 men were practising oro-anal sex, one used dental dams. In those providing both nasopharyngeal samples and sexual behaviour data meningococcal carriage was identified in 40 (17.5%) of the 228 men practising receptive oro-penile sex, compared with one (2.3%) of the 43 non-practisers (p < 0.025); in 21 (20%) of the 105 men practising insertive oro-anal sex, compared with 17 (12.5%) of the 136 non-practisers (p = 0.12). No correlation was identified between yeast carriage and oro-genital sex.

CONCLUSION

Oro-genital sex, usually without barrier protection, is common among HIV infected men who have sex with men. It appears to be associated with increased meningococcal carriage but is autonomous to candida species isolation. Routine screening for nasopharyngeal N gonorrhoeae is not deemed necessary.