Elena Visconti

Haemopoietic CD34+ progenitor cells are not infected by HIV-1 in vivo but show impaired clonogenesis

Summary. We evaluated the role of CD34 + bone marrow progenitor cells in vivo, in the pathogenesis of AIDS‐related haematological abnormalities. The clonogenic activity of CD34+ cells from seven patients with HIV‐1 infection, without bone marrow involving opportunistic infections or neoplasms, was assessed in semisolid cultures. The number of CFU‐GM was significantiy reduced as compared to the controls (P=0.017). independently from myelotoxic therapy, while the number of BFU‐E was not. The presence of retroviral sequences in CFU‐GM colonies from four patients and in the total population of CD34 + cells from six patients with advanced stage HIV infection was investigated using the polymerase chain reaction. The presence of HIV‐1 sequences was also searched for in a purified suspension of CD34 + cells after 3 weeks liquid culture. All these cells were always HIV‐1 negative, while viral sequences were always detected in bone marrow mononuclear cells from these and other patients. The number of HIV‐1 DNA copies decreased with increasing enrichment. At most 1:10000 CD34+ cells are infected in vivo. Other mechanisms than direct viral infection of progenitor cells must account for the defective haemopoiesis in HIV‐1 infected patients.

Variable efficiency of three primer pairs for the diagnosis of Pneumocystis carinii pneumonia by the polymerase chain reaction

The efficiency of three different primer pairs, complementary to different Pneumocystis carinii DNA regions, was compared in the polymerase chain reaction (PCR) for the diagnosis of Pneumocystis carinii pneumonia (PCP) on bronchoalveolar fluid (BALF) from patients with AIDS. PCR coupled with dot-blot hybridization (BLOT) using primers and probe from the mitochondrial 23SrDNA region showed the highest sensitivity, with a lower detection limit of 0.5-1 organisms microliter-1. When testing 47 BALF, PCR plus BLOT of the mitochondrial 23SrDNA region showed also the best diagnostic efficiency (97% sensitivity, 100% specificity). Sensitivity was significantly higher than with PCR and BLOT of the 5SrDNA region (81.5% sensitivity; P = 0.025, McNemar test); and of the dehydrofolate reductase (DHFR) gene region (75.6% sensitivity; P = 0.019). Sensitivity was also significantly higher than indirect immunofluorescence (75.8% sensitivity; P = 0.008). Using DHFR primers and probe, specificity was also reduced. The diagnostic sensitivity in clinical specimens paralleled the detection limit in the standard dilutions. The use of repeated DNA sequences of proven specificity as target of PCR amplification favourably influences sensitivity and specificity. This comparative study demonstrates that primer selection plays a significant role in the diagnosis of PCP by PCR.

Comparison of Two PCR Methods for Detection of Pneumocystis carinii in Bronchoalveolar Lavage Fluid

T h e identification of P. carinii DNA in respiratory samples i.e. induced sputum, bronchoalveolar lavage fluid or oropharyngeal secretions, by polymerase chain reaction (PCR) has been shown to be sensitive and specific. The diagnostic efficiency of PCR can be strongly influenced by the selection of the target DNA region to be amplified. In a previous study we cornpared the diagnostic efficiency of PCR using different primer pairs on bronchoalveolar lavage fluid from HIV-infected patients and we observed the best diagnostic efficiency using mitochondrial large subunit (mtLSU) rRNA primers and combining PCR with the BLOT technique [I] . Recently, Lu et al (41 developed a nested PCR method which amplifies internal transcribed spacers (ITS) of the ribosomal genes of human P. carinii (PC-ITS-PCR). Further, they referred to the PC-ITS-PCR as being the most effective method for the detection of PC in bronchoalveolar lavage specimens [ 5 ] . Recently, a nested PCR targeting the mtLSU gene has been Performed [7,8]. Aim of our study was to compare the efficiency of the nested PCR using mtLSU rRNA primers and of the nested PCR targeting ITS regions for diagnosis of P. carinii pneumonia in HIV infected patients. PATIENTS AND METHODS. Patients and clinical specimens. Bronchoalveolar lavage samples were obtained from 61 HIVinfected patients at the Department of Infectious Diseases, Universitb Cattolica S.Cuore, Roma. A11 patients undenvent bronchoscopy for an acute respiratory illness (fever, cough, shortness of breath) with one or more of the following features: abnormal chest signs, arterial specimens [p=.O8]. The first reaction of the PC-mtLSU-PCR and the PC-ITS-PCR gave positive results on 23 [loo%] and 7 [30.4%] of 23 P. corinii-positive BAL specimens, respectively [p=<.OOI].

Tubercular Osteomyelitis of the Second Metatarsal: A Case Report

A number of studies have described the osteoarticular involvement of tuberculosis, but very few cases of tubercular osteomyelitis of the foot have been reported. We describe a case of spina ventosa affecting the second metatarsal, with a review of the literature and description of the clinical manifestations, diagnostic images, and treatment of skeletal tuberculosis.

Lower hemoglobin levels in human immunodeficiency virus–infected patients with a positive direct antiglobulin test (DAT): relationship with DAT strength and clinical stages

BACKGROUND: There are conflicting opinions regarding the effect of positive direct antiglobulin test (DAT) on hemoglobin (Hb) levels in human immunodeficiency virus–infected (HIV+) patients.

Effect of HCV infection on glucose metabolism in pregnant women with HIV receiving HAART

Abstract Objective: A prospective study was designed to evaluate the prevalence and determinants of glucose metabolism abnormalities (GMAs) among HIV-1–infected pregnant women receiving highly active antiretroviral therapy (HAART). Methods: Blood samples were collected in fasting conditions and following a 100 g oral glucose tolerance test among HIV-infected pregnant women consecutively followed at asingle HIV reference centre in 2001–2008. GMAs were defined by glucose intolerance(IGT) or gestational diabetes (GDM), according to the National Diabetes Data Group criteria. Predictors of GMAs were assessed in univariate and multivariate analyses. Results: Overall, 78 women with no history of diabetes or GMAs were eligible for analysis. All were on stable HAART with either nevirapine or protease inhibitors (PIs) from at least 4 weeks at the time of sampling. GMAs during pregnancy were observed in 20 women (25.6%; GDM: 6, 7.7%; IGT: 14, 17.9%). In a multivariate analysis, after adjusting for age and ongoing antiretroviral treatment (PI or nevirapine), GMAs in pregnancy were significantly associated with HCV coinfection(adjusted odds ratio 4.16; 95% CI, 1.22–14.1;p = .022). No maternal or neonatalcomplications were observed. Conclusion: GMAs represent a relevant issue in the management of HIV-1–infected pregnant women. Our data suggest that these abnormalities are relatively common in this particular group. Women with HCV coinfection have an increased risk of developing GMAs during pregnancy and should be monitored for potential complications.

Typing with ITS regions of P. carinii from AIDS patients with recurrent pneumonia

To understand the way of reinfection of Pneumocystis carinii we have analyzed the genetic variation at the internal transcribed spacer (ITS) in DNA samples from bronchoalveolar lavage fluid of Italian HIV patients who had multiple episodes of P.carinii pneumonia. The presence of the same and/or a new type in both episodes suggest the possible occurrence of both reactivation of a previously acquired infection and reinfection from an exogenous source. Furthermore the occurrence of two different types in the same episode indicate that a mixed infection is common.

Pharmacokinetics of etravirine in HIV-infected patients concomitantly treated with rifampin for tuberculosis

Etravirine is metabolized by three cytochrome P450 enzymes that are in turn induced by rifampin. Consequently, co-administration of etravirine and rifampin is not recommended. To date, however, no clinical studies exploring the drug–drug interaction of this combination have been conducted. Here we report two cases of off-label etravirine use concurrently with antitubercular treatment, dictated by the unavailability of other treatments. Plasma drug concentrations were monitored by regular measurements. Our results appear to confirm the increased metabolism of etravirine through the induction of cytochrome P450 enzymes, but the adequacy of drug levels in all of the measurements and subsequent virological suppression suggest that this drug interaction may not be clinically relevant.

Combination antiretroviral therapy in human immunodeficiency virus-infected pregnant women

The conclusions of McGowan, et al (Obstet Gynecol 1999;94:641–6) may be questionable. A viral load change of 20.8 (22.6–0) log and a median viral load at delivery of 3.2 (2.6–5.2) log and an undetectable viral load at delivery in only 43% of women do not support “good control” of viral replication. In fact, these data may be considered criteria for changing therapy. Clinical deterioration, confirmed by AIDS-related events observed in two women, suggests antiretroviral therapy failure. Failure of a combination antiretroviral therapy may be related to many factors including altered absorption or metabolism of drugs (as may occur in pregnancy), multidrug pharmacokinetics (as may occur in drug addicts using methadone or benzodiazepines), or poor patient adherence. Active use of illicit drugs is undoubtedly related to poor adherence to therapy protocols and this may induce drug resistances. Therapeutic options may be greatly reduced after pregnancy. Moreover, we believe that active use of illicit drugs is a confounding factor for evaluating the effect of combination antiretroviral therapy on the newborn. From December 1997 to November 1999 we followed 12 non–drug-addicted pregnant women who used combination antiretroviral therapy (including protease inhibitors) and their newborns. Nine women achieved undetectable HIV RNA at delivery. Three women with incomplete adherence, a previous experience with zidovudine monotherapy (in two cases), and a noncontemporary starting of treatment had 0, 0.4, and 0.8 log HIV RNA reduction. The follow-up of these women is ongoing, but currently none has developed any HIVrelated event. Newborns exhibited low birth weight (z score 20.175, range 1.93 to 23.41); no major adverse events were observed at birth. HIV RNA and proviral DNA were negative in all infants at birth and in the evaluated babies at 6 months. The follow-up of these babies is ongoing, but no clinical events have developed yet. In our experience, combination therapy during pregnancy is useful for the control of maternal disease itself and in reducing vertical transmission of HIV. Thus, multicenter studies are needed to confirm the safety and the efficacy of such protocols.

Aetiological factors related to a positive direct antiglobulin test result in human immunodeficiency virus-infected patients

Background and Objectives  The aim of this study was to examine the clinical importance and causes of a positive result in the direct antiglobulin test (DAT) in human immunodeficiency virus‐infected (HIV+) patients. We therefore studied haematological parameters in outpatient samples, and also analysed the impact of highly active anti‐retroviral therapy (HAART) on the DAT results.