Estimation of biofilm, proteinase & phospholipase production of the Candida species isolated from the oropharyngeal samples in HIV-infected patients.

BACKGROUND & OBJECTIVES: Candida, the most common opportunistic infection in acquired immunodeficiency syndrome (AIDS), attributes its pathogenicity to its virulence factors, mainly the biofilms, the proteinases and the phospholipases. There is a significant interplay of these factors during the HIV infection. This study was aimed to estimate the biofilm, proteinase and phospholipase production in Candida species isolated from the oropharyngeal samples in the HIV-infected patients. METHODS: A total of 126 consecutive HIV-positive patients were screened for Candida growth using oropharyngeal swabs. Identification was done by Gram staining, germ tube test, chlamydospore identification, chromagar and biochemical tests on Vitek 2. Biofilm production was observed on Sabouraud's dextrose broth with glucose, phospholipase production in egg yolk agar medium and proteinase production in bovine serum albumin agar medium. RESULTS: Of a total of 126 patients, 53 (42.06%) showed Candida growth: Candida albicans (n=46, 86.8%) was most common followed by the non-albicans Candida (NAC) (n=7, 13.93%). Of a total 33 (62.3%) biofilm positive isolates, significant production was observed in the NAC species (P <0.05). C. albicans reported the highest phospholipase (n=37/41, 90.24%) and proteinase (n=37/43, 86%) activities in a total of 41 (77%) phospholipase positive and 43 (81.1%) proteinase positive isolates. INTERPRETATION & CONCLUSIONS: Although C. albicans was the most common Candida species identified in HIV positive patients, the emergence of NAC was of special concern. Virulence factors such as biofilms, proteinases and phospholipases were noted in both these groups. Further research is required for better understanding of the pathogenic role of Candida species so as to aid in therapeutic interventions.

Cryptococcal pleuritis containing a high level of adenosine deaminase in a patient with AIDS: a case report.

Cryptococcal infection is the 4th most common opportunistic infection in patients with acquired immune deficiency syndrome (AIDS). Although pleural effusion alone is an unusual presentation, we present a case of cryptococcal pleuritis in an AIDS patient which was initially difficult to discriminate from tuberculous pleuritis because of the high level of pleural adenosine deaminase (ADA). Cryptococcus neoformans was detected in the culture of the pleural effusion after the initiation of antituberculous treatment. High levels of ADA in the pleural fluid can be observed in patients with cryptococcal pleuritis, and longer incubation of pleural fluid should be performed in all patients who present with pleuritis associated with a high ADA level as the only significant finding.

Matrix metalloproteinases, their production by monocytes and macrophages and their potential role in HIV-related diseases.

Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases that are a subfamily of metzincins. Matrix metalloproteinases are responsible for much of the turnover of extra-cellular matrix components and are key to a wide range of processes including tissue remodeling and release of biological factors. Imbalance between the MMPs and endogenous tissue inhibitors of metalloproteinases (TIMPs) can result in dysregulation of many biologic processes and lead to the development of malignancy, cardiovascular disease, and autoimmune and inflammatory disorders. MMP production by monocyte/macrophages is dependent on the cell type, state of differentiation, and/or level of activation and whether they are infected, e.g., by HIV-1. MMP expression by HIV-1 infected monocytes and macrophages may alter cellular trafficking and contribute to HIV-associated pathology such as HIV-associated dementia (HAD). This review will provide a classification of the MMP super-family with particular reference to those produced by monocyte/macrophages, describe their regulation and function within the immune system, and indicate their possible roles in the pathogenesis of disease, including HIV-associated dementia.

Extracellular enzymatic activities in Cryptococcus neoformans strains isolated from AIDS patients in different countries.

Three hundred and ten Cryptococcus neoformans strains isolated from AIDS patients in five different countries (151 from Brazil, 23 from Italy, 28 from Spain, 104 from Thailand and four from Turkey) were tested by the API-ZYM kit to detect their extracellular enzymatic activity. The enzymes esterase (C4) (no 3), esterase lipase (C8) (no 4), leucine arylamidase (no 6) and acid phosphatase (no 11) were commonly positive in most of the strains (more than 95%). These enzymes could be considered a useful tool not only for C. neoformans identification, but in particular for their possible relationship to new C. neoformans virulence factors and also for epidemiological research. Interestingly, it is also the high positive percentage of alpha-glucosidase and beta-glucosidase detected in all isolates. The serotype A was the most predominant serotype in all countries, except for Italy where the serotype D was predominant. Further studies are needed to draw a clear correlation between the API-ZYM profile and serotype.

Differential activation of the extracellular signal-regulated kinase, Jun kinase and Janus kinase-Stat pathways by oncostatin M and basic fibroblast growth factor in AIDS-derived Kaposi's sarcoma cells.

OBJECTIVES: To determine the integration of signalling pathways associated with two recognized Kaposi's sarcoma (KS) growth factors, oncostatin M (OSM) and basic fibroblast growth factor (bFGF), in the induction of KS cell proliferation. DESIGN AND METHODS: We used protein kinase assays, protein-DNA interactions and AP-1 luciferase assays to study the extracellular signal-regulated kinase (ERK), Janus kinase (JAK)-Stat and Jun kinase (JNK) pathways in AIDS-derived KS cells during stimulation with OSM and bFGF. RESULTS: Treatment with OSM-induced activation of receptor-associated JAK and phosphorylation of Stat1 and Stat3. Stat1/Stat3 heterodimers interacted with known gamma-interferon-activated sites like elements such as the sis-inducible element (SIE) in the C-fos promoter. In contrast, ligation of the bFGF receptor induced Stat3 phosphorylation and its association with the bFGF receptor, but failed to induce JAK activity or protein complexes which interact with GAS-like oligonucleotides. OSM also induced the activation of ERK2 by activating the serine/threonine kinases Raf-1 and [mitogenactivated protein kinase (MAPK) ERK kinase (MEK1)]-1, while bFGF failed to activate any of the above components. Both OSM and bFGF activated the JNK pathway, along with the activation of MEKkinase (MEKK)-1. JNK control the transcriptional activation of c-Jun. Because the above pathways exert an effect on the expression or activation of activation protein (AP)-1 components, we confirm that OSM and bFGF induce TPA response element (TRE)-luciferase activity synergistically. CONCLUSION: We demonstrate that OSM and bFGF activate distinct as well as shared signalling cascades in KS cells, which integrate to provide a synergistic AP-1 response by which OSM and bFGF may sustain KS cell growth.

Role for Raf in the entry of viruses associated with AIDS (review).

The biology of acquired immune deficiency (AIDS) is yet to be completely understood partly because it is complicated by the manifestation of various viral infections and associated pathogenesis. Virus entry into target cells is a key step in the virus replication cycle which is characterized by intricate and complex interactions between virus and host cells. Analyses of virus entry are always hampered to some extent due to the inability to mimic in vivo conditions. Emphasis has been placed on understanding what the virus does during the entry process; for example the signaling it mediates during entry, or identifying the cellular receptors with which the virus interact. Often, the role of the cellular environment that is critical for the complex process of virus uptake has taken a back stage. Interestingly, most of the viruses associated with AIDS cause tumors. In a recently concluded study, we identified a role for intracellular oncogenic (Raf) signaling in human herpesvirus-8 (HHV-8/KSHV) infection of target cells. In this review we present an update on entry of various viruses commonly associated with AIDS and yet another novel way of analyzing virus entry.

Multisystem organ failure predicts mortality of ICU patients with acute respiratory failure secondary to AIDS-related PCP.

OBJECTIVE: To evaluate the ability of a variety of scoring systems to predict mortality of patients admitted to an intensive care unit (ICU) with acute respiratory failure (ARF) secondary to AIDS-related Pneumocystis carinii pneumonia (PCP). METHODS: All patients with AIDS-related PCP admitted to ICU at St. Paul's Hospital between January 1, 1985 and April 1, 1991 were reviewed. For each case, the following scores were calculated from data obtained within 24 h of ICU admission: acute physiology and chronic health evaluation II (APACHE II); acute lung injury score; AIDS score as described by Justice and Feinstein; and modified multisystem organ failure (MSOF) score. The serum lactate dehydrogenase (LDH) level was also recorded when obtained within 24 h of ICU admission. RESULTS: A total of 52 ICU admissions in 51 patients were studied. Overall mortality was 65 percent. Mortality increased with increasing MSOF (p < 0.05) score and LDH (p < 0.05). Based on receiver operating characteristic (ROC) curves, the MSOF score and the LDH were found to be good predictors of mortality. Multivariate logistic regression showed that the MSOF score was the only independent predictor of mortality (p < 0.05). The AIDS score, APACHE II, and the acute lung injury score were not significantly associated with mortality. Addition of the serum LDH level improved the performance of both the MSOF and AIDS scores, though the AIDS score plus LDH performed no better than the LDH alone. Of all the scores tested, the MSOF plus LDH level was the best (p < 0.005) predictor of mortality. CONCLUSIONS: The modified MSOF score and the serum LDH level are the best predictors of mortality of patients admitted to ICU with ARF secondary to AIDS-related PCP. The performance of the MSOF score was enhanced when the LDH level was added. The AIDS score, APACHE II, and the acute lung injury score were not found to be useful in this group of critically ill patients.

Utility of lactate dehydrogenase vs radiographic severity in the differential diagnosis of Pneumocystis carinii pneumonia.

STUDY OBJECTIVES: In patients with HIV infection, serum lactate dehydrogenase (LDH) level is commonly stated to be more elevated in Pneumocystis carinii pneumonia (PCP) than in non-PCP. We hypothesized that LDH level reflects radiographic extent and severity of pneumonia rather than P carinii infection specifically and therefore is not useful in the differential diagnosis of lung infections in AIDS. DESIGN: We compared radiographic features and LDH values in 93 sequential patients with HIV infection and a new hospital admission for pneumonia (53 PCP and 40 non-PCP) after excluding all patients with other potential causes for elevated LDH levels. The chest radiograph was graded using a quantitative scale (0 to 24) to assess radiographic extent and severity of pneumonia by two independent observers in blinded fashion. The relationship between radiographic score and hospital admission LDH level was analyzed by linear regression and Bayesian analysis was applied to different LDH ranges to calculate the clinical value of LDH measurements. SETTING: Tertiary care teaching hospital and regional AIDS referral center. RESULTS: Mean LDH level was higher in the PCP group (1.217 +/- 88 U/L compared with 776 +/- 55 U/L; p < 0.001), as was mean radiographic score (12.4 +/- 0.6 for PCP compared with 6.3 +/- 0.5 for non-PCP; p < 0.001). For the whole sample of 93, LDH level was significantly related to chest radiographic score (r = 0.43, p < 0.0001). Significant overlap occurred between the two groups at all levels of LDH such that no cutoff level could be established that impacted significantly on posttest probability of PCP, whereas a radiographic score of > 12 yielded a 96% posttest probability of PCP. CONCLUSIONS: Serum LDH level reflects the degree of radiographic abnormality and is elevated in both PCP and non-PCP pneumonia to an extent that limits its utility in differentiating the two processes in hospitalized patients. The extent of radiographic involvement more clearly distinguishes the two conditions.

Elevated adenosine deaminase activity in patients with HIV and tuberculous peritonitis.

OBJECTIVE: To evaluate the diagnostic potential of the ADA(T), ADA isoenzymes (ADA1 and ADA2) and the interferon-gamma (IFN-gamma) test in HIV-seropositive patients with tuberculous peritonitis. METHODS: Ascitic ADA(T), ADA1, ADA2 and IFN-gamma were prospectively evaluated in HIV-seronegative patients with tuberculous peritonitis (n = 17), HIV-seropositive patients with tuberculous peritonitis (n = 6) and in patients with cirrhosis (n = 22) and malignancy (n = 5). RESULTS: ADA(T) and ADA2 isoenzyme activities of HIV-seronegative (ADA(T) = 109 U/l; ADA2 = 94 U/l) and HIV-seropositive (ADA(T) = 109.5 U/l; ADA2 = 95.5 U/l) patients with tuberculous peritonitis, respectively, were significantly different (P < 0.001) from patients with cirrhosis (ADA(T) = 10.5 U/l; ADA2 = 8 U/l) and malignancy (ADA(T) = 13 U/l; ADA2 = 11 U/l). There was no significant difference in ADA(T) and ADA2 activities between HIV-seropositive and seronegative patients with tuberculous peritonitis. There was no significant correlation between ADA, its isoenzymes and IFN-gamma. CONCLUSIONS: The diagnosis of tuberculous peritonitis can be made by a sensitive, relatively non-invasive procedure in both HIV-seronegative and seropositive patients with minimal risk to the patient and the investigator. The diagnostic value of ADA(T) is not enhanced by measuring ADA isoenzymes or IFN-gamma.

The association of serum lactate dehydrogenase level with selected opportunistic infections and HIV progression.

BACKGROUND: The purpose of this study was to determine the association of serum lactate dehydrogenase (LDH) levels with certain opportunistic infection and to determine an association between LDH levels and CD4+ lymphocyte counts. METHOD: We studied 352 patients retrospectively with HIV infection and one of the following infections: histoplasmosis; toxoplasmosis; tuberculosis (pulmonary and disseminated); bacterial pneumonia; Pneumocystis carinii pneumonia. Demographic and clinical data were obtained from the Adult Spectrum of Diseases (ASD) database in New Orleans. Bivariate and multivariate analysis were used to determine the association between LDH levels and opportunistic infections and CD4+ lymphocyte counts. RESULTS: Patients with a serum LDH level <225 IU/L had a mean CD4+ lymphocyte count of 159/dl (SE 19.3) as compared to patients with a serum LDH level > or =225 IU/L, who had a mean CD4+ lymphocyte count of 58/dl (SE 6.9) (P<0.01). Non-Caucasian race, a diagnosis of histoplasmosis, disseminated tuberculosis or Pneumocystis carinii pneumonia, and CD4+ lymphocyte count were significantly associated with a serum LDH level > or =225 IU/L in the bivariate analysis. In a multivariate analysis, after controlling for race and CD4+ lymphocyte count, the only diagnoses that were significantly associated with the serum LDH level were definitive Pneumocystis carinii pneumonia and toxoplasmosis. Having a higher LDH level was not associated with early mortality. CONCLUSIONS: Although not diagnostic, serum LDH levels could be used as an adjunctive marker in certain opportunistic infections. There is an inverse relationship between serum LDH levels and CD4+ lymphocyte counts in this group.

Impact of amphotericin B on the cytochrome P450 system in HIV-infected patients.

OBJECTIVE: To investigate whether cytochrome P450-dependent enzymes are influenced by amphotericin B (Am-B) during the treatment of Candida oesophagitis in HIV-infected patients. METHODS: Twelve HIV-infected, antiretroviral-naive patients (CDC/WHO stage C3) with Candida oesophagitits were enrolled into a prospective clinical trial. The patients were treated with Am-B (0.4 mg/kg body weight) for two weeks. At baseline and after Am-B therapy the clearance of antipyrine and its metabolites were investigated by high-performance liquid chromatography. In addition, the urinary excretion of 6-beta-hydroxycortisol and 17-hydroxycorticosteroids was assessed by means of a radioimmunoassay. RESULTS: The following significant changes were observed after Am-B treatment (P < 0.01): increase of antipyrine half-life (12.4 h vs 16.8 h) and the area under the plasma concentration-time curve (27.9 mg min/ml vs 38.1 mg min/ml); decrease of the total body clearance (61.2 ml/min vs 43.7 ml/min); decrease of the renal clearance of antipyrine metabolites - norantipyrine (7.45 ml/min vs 5.31 ml/min), 4-hydroxyantipyrine (15.4 ml/min vs 10.3 ml/min), hydroxymethylantipyrine (4.31 ml/min vs 3.65 ml/min); decrease of urinary 6-beta-hydroxycortisol excretion (453 microg/24h vs 298 microg/24h) and the ratio of 6-beta-hydroycortisol to 17-hydroxycorticosteroids (8.8% vs 6.4%). CONCLUSIONS: Our data indicate that Am-B therapy has an inhibitory effect on cytochrome P450-dependent enzymes in HIV-infected patients. These results are of particular significance for HIV-infected patients who are concomitantly treated with drugs that are predominantly metabolised in the liver. A careful drug monitoring system seems advisable, especially for proteinase inhibitor experienced HIV-1-infected subjects.

Serum LDH level as a clue to the diagnosis of histoplasmosis.

The purpose of this study was to determine whether serum lactate dehydrogenase (LDH) level could be used as an adjunct clinical marker to differentiate between histoplasmosis and Pneumocystis carinii pneumonia (PCP). In a retrospective, case-controlled study, 30 patients with a diagnosis of histoplasmosis (all but 1 with disseminated disease) were compared with 120 patients with PCP (33 patients with definitive PCP, 87 with presumed PCP). Groups were matched for CD4+ lymphocyte counts, sex, and year of diagnosis. The mean LDH level for patients with histoplasmosis was 1068 +/- 197 IU/L; for PCP, it was 375 +/- 23. An LDH level of more than 450 IU/L was 9.33 times more likely to be associated with a diagnosis of histoplasmosis than with PCP (odds ratio [OR], 9.33; 95% confidence interval [CI], 3.50-25.47; P < .01), and an LDH level of more than 600 IU/L was 9.41 times more likely to be so (OR, 9.41; 95% CI, 3.43-26.31; P < .01). An LDH level of 450 IU/L or greater had a sensitivity and specificity of 70% and 80%, respectively; a value of 600 IU/L or greater had sensitivity and specificity of 50% and 89%. Thus, serum LDH levels of 600 IU/L or greater are suggestive of histoplasmosis rather than PCP in appropriate clinical settings. Serum LDH may serve as an adjunct laboratory marker in the diagnosis of histoplasmosis. Elevated levels may prompt the physician to look for a diagnosis other than PCP early in the course of the illness.

Initial treatment with amphotericin B plus rifampin in the acute treatment of cryptococcal meningitis in aids.

The result of initial treatment with amphotericin B (0.7 mg/kg/day) plus rifampin (600 mg/day) for 2 weeks, followed by fluconazole (400 mg/day) for 8 weeks in the acute treatment of cryptococcal meningitis in AIDS is reported. There were 10 patients in the study: at 2 weeks, all had made a clinical response and cerebrospinal fluid was sterile in 4 patients; at 10 weeks, all had negative cerebrospinal fluid cultures. Serious side effects were not detected.

[Adenosine deaminase in the cerebrospinal fluid of patients with acquired immunodeficiency syndrome]. / Adenosino-deaminase no líquido celalorraqueano de pacientes com a síndrome da imunodeficiência adquirida.

The adenosine-deaminase (ADA) activity was evaluated in CSF samples from 263 patients with AIDS. An elevated ADA activity in CSF was found in patients with: antibodies to toxoplasmosis, syphilis or cytomegalovirus; Cryptococcus neoformans or their antigens; tuberculous meningitis; lymphoma. There was no statistical difference among all these groups in respect to ADA activity. However, the ADA activity in CSF from AIDS patients without CSF changes other than HIV antibodies, even unspecific changes, was not elevated. This may suggest that ADA is related to AIDS associated pathologies activity rather than to HIV infection itself.

[Histoplasma capsulatum in the peripheral blood of patients with AIDS. Report of 4 cases with an increase of lactate dehydrogenase]. / Histoplasma capsulatum en sangre periférica de pacientes con SIDA. Informe de cuatro casos con elevación de deshidrogenasa láctica.

This paper describes the clinical course of four patients with AIDS who were found to have H capsulatum in peripheral blood. The evolution of the infection was fulminant and all died within the first 96 hours following hospitalization. In every case the presence of the characteristic mycelium and "tuberculate" macroconidia of Histoplasma was established in cultures. All cases showed the hematological abnormalities common in other AIDS associated diseases. In addition, there was an increase in serum lactic dehydrogenase over ten times our normal level: the lowest LDM assay was 2137 IU/mL and the highest 4839 IU/mL. This clinical course resembling septicemia and the demonstration of H capsulatum in a peripheral blood smear has had a rate of 12% in our experience (four out of the 34 cases of AIDS with histoplasmosis seen in our institution from January 1984 to March 1991).

[Levels of serum lactate dehydrogenase and its isozymes with relation to clinical features of pneumocystis carinii pneumonia in acquired immunodeficiency syndrome patients].

The clinical courses of 9 patients with acquired immunodeficiency syndrome (AIDS) complicated by pneumocystis carinii pneumonia (PCP) were followed to investigate the clinical significance of the measurement of various parameters such as serum lactate dehydrogenase (LDH). The mean duration of symptoms before diagnosis was 20 days, and the median duration of therapy was 29.5 days. Serum LDH activity increased in 8 of 9 cases. The isozyme pattern in all cases was characterized by high LDH3 values from the early stage. However, inflammatory markers did not increase in most cases. There were good correlations between the levels of LDH, clinical course, and PaO2.

Phase II trial of imatinib in AIDS-associated Kaposi's sarcoma: AIDS Malignancy Consortium Protocol 042.

PURPOSE: Kaposi's sarcoma (KS) is a disease of multifocal vascular proliferation that requires infection with KS herpes virus (KSHV/HHV-8). Activation of the c-kit and platelet-derived growth factor (PDGF) receptors by autocrine/paracrine mechanisms follows endothelial cell KSHV infection. In a pilot study, imatinib, a c-kit/PDGF-receptor inhibitor, induced partial regression of AIDS-associated KS (AIDS-KS) in five of 10 patients. PATIENTS AND METHODS: This multicenter phase II study was designed to estimate the response rate to imatinib in AIDS-KS. Secondary objectives included investigation of predictors of response and imatinib pharmacokinetics in patients on antiretrovirals. Patients received imatinib 400 mg/day by mouth for up to 12 months with dose escalation up to 600 mg/day at 3 months if their disease was stable. RESULTS: Thirty patients were treated at 12 AIDS Malignancy Consortium sites. Ten patients (33.3%) achieved partial response, six (20%) had stable disease, and seven (23.3%) exhibited KS progression. Nine patients completed 52 weeks of imatinib therapy. The median treatment duration was 22.5 weeks. Only five patients (16.7%) discontinued therapy owing to adverse events. Antiretroviral regimens did not significantly alter imatinib metabolism. Activating mutations in PDGF-R and c-kit were not found at baseline or at disease progression. We found no correlation with response with changes in any of the candidate cytokines. CONCLUSION: Imatinib has activity in AIDS-KS. Pharmacokinetic interactions with antiretroviral drugs did not correlate with toxicity. Thirty percent of patients showed long-term clinical benefit and remained on imatinib for the entire year. These results suggest imatinib is well tolerated and may be an alternative therapy for some patients with AIDS-KS.

Markedly elevated serum lactate dehydrogenase levels are a clue to the diagnosis of disseminated histoplasmosis in patients with AIDS.

Disseminated histoplasmosis is a common late manifestation of AIDS, but the diagnosis may be unsuspected in some patients because the clinical presentation of histoplasmosis may mimic other opportunistic infections. High serum lactate dehydrogenase (LDH) levels have been associated with disseminated histoplasmosis. We therefore evaluated whether markedly increased LDH levels were useful for making a diagnosis of disseminated histoplasmosis by comparing admission LDH levels for 15 patients with culture-proven disseminated histoplasmosis with those for 30 patients with advanced AIDS who were admitted to the hospital for evaluation of pulmonary infiltrates and fever. The mean admission LDH level in patients with disseminated histoplasmosis was 1,356 IU/L (range, 145-5,410 IU) whereas it was 332 (range, 77-832 IU) in the patients with other pulmonary processes. Admission LDH levels were >600 IU in 11 (73%) of the 15 patients with disseminated histoplasmosis vs. 3 (10%) of controls (P < .001). We conclude that markedly elevated admission LDH levels may be a clinical clue to the diagnosis of disseminated histoplasmosis in patients with AIDS.