Chlamydia pneumoniae respiratory infections among patients infected with the human immunodeficiency virus

Thirteen cases of Chlamydia pneumoniae infection in patients seropositive for the human immunodeficiency virus (HIV) are described. The occurrence, the clinical spectrum, and the significance of the infection during HIV disease are compared with data reported in the literature. Chlamydia pneumoniae infection was established by a serologic micro-immunofluorescence test using standard diagnostic criteria. In four cases the results of serological tests were confirmed by direct immunofluorescence on respiratory specimens. Five patients developed focal pneumonia but recovered completely after specific antibiotic treatment. Three patients developed severe and diffuse interstitial pulmonary involvement, two of whom died of acute respiratory failure. Five patients developed upper respiratory tract infection. Using 39 pair-matched HIV-seropositive subjects as controls, the cases of infection were found to be significantly associated with a previously diagnosed pulmonary disease. Upon retrospective analysis of 319 consecutive cases of pneumonia among HIV-infected patients, Chlamydia pneumoniae was the sole agent detected in eight (2.5%) cases, and Chlamydia pneumoniae together with other infectious agents was detected in seven (2.2%) cases. Chlamydia pneumoniae is a possible cause of severe respiratory infection in Italian HIV-infected immunocompromised patients, and its presence must be suspected when patients do not respond to therapy with beta-lactam agents or to anti-Pneumocystis carinii treatment.

Biological correlates of HIV-1 heterosexual transmission

OBJECTIVES

To study the role of HIV-1 biological phenotype, viral load and neutralizing antibodies in male-to-female heterosexual transmission of HIV-1.

METHODS

Seven transmitting and seven non-transmitting HIV-1-seropositive heterosexual male index cases were included in the present study. All couples had engaged in unprotected sex for a period of over 1 year. Transmission was defined by the seroconversion of the female sexual partner. Virus isolates were tested in MT-2 cells for replication and syncytia induction. HIV-1 RNA plasma load was measured by the branched DNA technique. Serum neutralizing activity to primary HIV-1 isolates was tested by using peripheral blood mononuclear cells (PBMC) as target cells.

RESULTS

Non-transmitting index cases had a lower HIV-1 RNA concentration in plasma than transmitting index cases. Non-transmitting index cases also tended to have serum neutralizing activity with broad specificity and to have viruses with low replicative capacity, as characterized by 50% infectious dose titres in PBMC and by the lack of MT-2 tropism.

CONCLUSIONS

The results indicate that plasma viral-RNA load is a marker for transmission. Moreover, an interplay between the host immune response and viral replication may modulate the level of viral load and thereby influence HIV-1 transmission.

Markers of response to zidovudine monotherapy among treated HIV seroconverters. Italian Seroconversion Study

The aim of the study was to evaluate indicators of response to zidovudine monotherapy in terms of progression to AIDS and death in a cohort of human immunodeficiency virus (HIV) seroconverters. From a larger observational epidemiological cohort of 1,024 HIV seroconverters we identified 315 persons on zidovudine monotherapy. In this treated cohort, age, sex, risk group, constitutional symptoms, CD4 cell count, and p24 antigen levels at initiation of treatment and 6 months later were examined separately for two outcomes, AIDS and death, using standard survival methods. The variables measured at the visit at which zidovudine monotherapy was initiated that predicted more rapid progression to AIDS were CD4 cell count (RH = 2.61); constitutional symptoms (RH = 2.56); p24 antigenaemia level (RH = 2. 17); and subsequent change in CD4 cell count (> 30% decline) contributed additional predictive information (RH = 2.70). Results were similar for mortality, and did not vary significantly by risk group. In a tested subset of patients, p24 antigenaemia was associated with high levels of plasma RNA viral load. The median number of HIV RNA copies was about 28,000 copies/ml among p24 antigen-positive individuals and about 7,700 copies/ml among participants who were persistently negative for p24 antigenaemia. CD4 cell count, symptoms and p24 antigenaemia at the start of therapy and CD4 cell decline after initiation of treatment are early indicators of disease progression in zidovudine-treated patients. The combined use of these indicators may help to better predict who will respond to zidovudine or to other antiretroviral therapies.

Giardiasis in HIV: a possible role in patients with severe immune deficiency

We report the epidemiological, clinical and therapeutic characteristics of giardiasis in a population of HIV-infected patients with diarrhoic syndrome. During the period between 1988 and 1995, 720 HIV-patients with diarrhoic syndrome were evaluated. Fecal specimens were submitted to parasitological examination according to the Ritchie formalin-ethil acetate centrifugal sedimentation method and stained with iodine. Samples also underwent modified Ziehl-Neelsen staining and standard bacteriologic testing. Cystis of G. intestinalis were identified in stool sample of 25 patients. Two patients were classified as in stage A2 and 23 in C3. Mean CD4 values of patients with giardiasis (26.9 cells/mmc) were compared with those of 65 patients from whom, during the study, was isolated Cryptosporidium parvum (63.12, cells/mmc): the difference resulted highly significant (p < 0.001). Among the patients with full-blown AIDS, giardiasis occurred following a single previous AIDS-defining event in 13 inividuals, in seven and in five subjects giardiasis was the 3rd and, respectively, the 4th relevant AIDS-defining condition. Death occurred within the following 2 months in nine patients and within 6, 12 and 24 months in seven, six and two patients, respectively; at present only three AIDS patients are still alive. In general, G. intestinalis in HIV+, is not considered a major cause of enteritis; nevertheless, in our experience enteritis due to G intestinalis is a frequent event among AIDS patients, especially in the most advanced stage of disease, irrespectively of the risk factor. The increase in mean survival of AIDS patients will probably lead to a progressive emergence of this pathogen which could determine a severe diarroic syndrome with hydro-electrolytic impairments.

How many HIV-infected individuals may be defined as long-term nonprogressors? A report from the Italian Seroconversion Study. Italian Seroconversion Study Group (ISS)

We prospectively examined a cohort of HIV-positive persons with an accurately estimated date of HIV seroconversion who were infected through injecting drug use or sexual contact to estimate the proportion of long-term nonprogressors (LTNP), considering four definitions of LTNPs. We also evaluated whether factors such as gender, age, and HIV-exposure category were associated with being LTNP; we determined the overlap among the definitions and compared the CD4 and CD8 counts and the CD4/CD8 decline among LTNPs and "moderate" and "fast" progressors. Of the 528 persons selected for analysis, 2 to 4% were considered LTNPs, depending on the definition. The proportion of LTNPs varied by definition, and there was little overlap among definitions. The LTNPs did not appear to differ from "moderate" and "fast" progressors with regard to main demographic characteristics, and they showed a better trend of immunological parameters, appearing to have a slower progression rather than a permanently arrested infection.

Italian multicentre study of didanosine compassionate use in advanced HIV infection. Italian BMS-906 Study Group

The aim of the present study, a multicentre trial of didanosine (ddI) compassionate use, was to identify factors associated with a better outcome in patients given ddI monotherapy. Enrolled were 1047 HIV-positive patients intolerant of and/or unresponsive to zidovudine (ZDV) therapy, with CD4+ cell counts of < 200/microliter or AIDS. Didanosine was given at a dose of 250 mg b.i.d. (patients > or = 60 kg) or 167 mg b.i.d. (patients < 60 kg). Clinical examinations and laboratory tests were performed every two months. Endpoints included death, the occurrence of a new AIDS-defining disease, or permanent discontinuation of ddI for a severe adverse event. At entry, the median CD41 cell count was 47/microliter and the median duration of prior ZDV treatment 19 months; 446 patients (43%) were classified as having AIDS. Severe toxicity occurred in 143 subjects (14%); the frequency of pancreatitis was very low (0.2%). The benefit in terms of CD4+ cell counts was greater for patients whose counts exceeded 100/microliter at entry and remained at this level until month 12 in those patients still receiving treatment. Death and/or new AIDS-defining events were observed in 374 cases (36%) over a median follow-up of eight months. AIDS dementia was observed in 11 patients (1%). Multivariate analysis of survival without disease progression showed that the factors associated with a worse outcome include the severity of immunodepression, a diagnosis of AIDS at entry, and a history of both intolerance of and clinical resistance to ZDV. Surprisingly, the patients who had received previous prolonged treatment with ZDV had a better outcome. In conclusion, severely immunodepressed patients previously administered long-term monotherapy may receive a short-term benefit from being switched to another antiretroviral drug.

Familial clustering of HBV pre-C and pre-S mutants

BACKGROUND/AIMS

Little is known about the persistence and risk of infection with hepatitis B viruses (HBV) containing mutations in the pre-C and pre-S region. The aim of this study was to study the long-term persistence and the risk of intrafamilial spreading of these variants.

METHODS

Serological markers were analyzed immunologically and pre-C and pre-S sequences of HBV DNA in sera from several members of five families by DNA amplification and direct sequencing.

RESULTS

In most HBV-DNA positive individuals of each family, either the dominant HBV population or a subpopulation had a stop codon in the pre-C region which prevented expression of e-antigen. The pre-S region of the dominant virus populations of 8/15 HBV-DNA positive sera showed different deletions or a pre-S2 translation initiation codon mutation in addition to various point mutations. Selection for pre-C and pre-S mutant viruses from a predominant "wildtype" virus population was observed in three individuals during the natural course of infection. Persistence of a pre-C/pre-S double mutant virus as a stable strain for 6 years was found in one patient.

CONCLUSIONS

These data indicate extensive intrafamilial clustering of HBV variants with mutations in the pre-C and pre-S regions due to patient-specific selection mechanisms and long-term persistence of some mutants as stable strains. The type of viruses found suggests that occasionally virus subpopulations are selectively transmitted or become a dominant virus population after selection.

Lymphogranuloma venereum: a case report in an Italian traveller

A 38-year-old man with a recent history of travel in India and unprotected sexual intercourse with Indian women, was admitted with painful enlarged lymphnodes predominantly in the right inguinal area. Diagnosis of lymphogranuloma venereum was made by means of a positive immunofluorescence test (Total Ig titer of 1:512) and a positive detection of chlamydial antigens by ELISA in a semen sample. He was successfully treated with ciprofloxacin. This observation emphasizes the relevance of infection due to C. trachomatis serotypes L1-L3 that may be acquired during travel in developing countries.

Topical thymopentin therapy in HIV positive patients with recurrent oral candidiasis: a pilot study

Oral candidiasis frequently occurs in HIV-positive patients especially in those with advanced disease. To date, common anti-mycotic drugs are unable to prevent relapses and alternative therapy is necessary to reduce disabling effects. With the aim of verifying whether thymic hormone extract may be efficacious in these subjects, we enrolled 10 HIV-positive patients with recurrent and/or persistent oral candidiasis to be treated with thymopentin (oral inhalations). All patients benefited from the topical use of thymopentin, and in all cases there was marked increase in salivary secretory IgA which possibly accounted for the candidiasis improvement.

A randomized controlled trial of a protease inhibitor (saquinavir) in combination with zidovudine in previously untreated patients with advanced HIV infection

This study assessed the activity and tolerability of an HIV-protease inhibitor, saquinavir, alone or in combination with zidovudine. A total of 92 previously untreated HIV-infected patients with CD4 cell counts < 300 cells/mm3 participated in a parallel, randomized double-blind study. Patients were randomized to receive one of five treatments, each three times a day: 600 mg of saquinavir; 200 mg of zidovudine; 75, 200 or 600 mg of saquinavir in combination with 200 mg of zidovudine. The primary treatment period was 16 weeks, with monthly extensions in patients who did not show major disease progression or toxicity. The main measures of the efficacy of therapy used were changes in CD4 cell counts and in the concentration of HIV-1 RNA in the plasma (as determined by quantitative polymerase chain reaction). The 600 mg dose of saquinavir in combination with zidovudine induced a 1.6 log (after 4 weeks) and a 0.7 log (after 16 weeks) median reduction in plasma RNA concentration; this reduction was greater than those seen in the other four treatment groups. The combination of 600 mg of saquinavir with zidovudine also resulted in a larger and more sustained improvement in the CD4 cell count than either saquinavir or zidovudine monotherapy or the other combination therapies. In the group receiving 200 mg of saquinavir in combination with zidovudine, the maximal median change in CD4 cell count occurred at week 2 (85 cells/mm3), and by week 16 had fallen to 15 cells/mm3. In the group receiving 600 mg of saquinavir plus zidovudine, the median change in CD4 cell count remained high for the 16-week period (median change of 48 cells/mm3 at week 2 and 61 cells/mm3 at week 16). Saquinavir was safe and very well tolerated, either alone or in combination with zidovudine. The incidence of adverse events was greater in the four groups receiving zidovudine therapy, and all the most commonly reported adverse events have previously been associated with zidovudine therapy. Few changes in laboratory values occurred during the study, except for known zidovudine-associated toxicities. The most frequent abnormalities were raised aspartate aminotransferase and alanine aminotransferase levels, depressed calcium levels, and abnormally high or low phosphate levels. Despite the low oral bioavailability of saquinavir, combined virological and immunological data show definite antiviral activity in vivo for the combination of saquinavir at 600 mg plus zidovudine at 200 mg (each three times daily). The combination of drugs with different mechanisms of action represents an advance in the treatment of HIV infection.

The role of HIV type 1 phenotype and genotype in long-term responders to zidovudine therapy

We performed a cross-sectional and partly retrospective virological evaluation of 31 long-term responders (LTRs) to zidovudine (ZDV) (persistent increase in the CD4+ cell counts without progression of HIV infection throughout a period of ZDV therapy > 3 years) and 17 well-matched controls who developed a marked immunological deterioration over a 24-month period of ZDV therapy. The biological phenotype of HIV-1 was assessed by testing the capacity of the isolates to replicate in the MT-2, HUT-78, C-8166, and U-937 T cell lines, and mutations at codons 215 and 41 of RT were checked in proviral DNA from uncultured PBMCs. Show/low non-syncytium-inducing (S/L-NSI) and rapid/high syncytium-inducing (R/H-SI) variants were detected in 25 (81%) and 2 (6%) LTRs, respectively. HIV-1 could not be isolated in the remaining four LTRs (13%). Conversely, 12 of 17 (71%) controls yielded R/H-SI variants. Conversion from the S/L-NSI to R/H to R/H-SI phenotype occurred in 5 controls but in none of the 18 LTRs tested. Mutant sequences in proviral DNA from control PBMCs were consistently detected (94%), while a wild-type sequence of the residues investigated was found in the majority of LTRs (77%). In our series, patients who received immunological and clinical benefits even after prolonged ZDV treatment had S/L-NSI viruses and a low risk to develop ZDV resistance. Conversely, subjects who demonstrated an immunological and clinical deterioration yielded R/H-SI variants or shifted from S/L-NSI to R/H-SI phenotypes and were at higher risk to develop mutations indicating ZDV resistance.

Choreoathetosis in acquired immune deficiency syndrome patients with cerebral toxoplasmosis

The aim of our study was to evaluate both the incidence and the pathologic and clinical features of extrapyramidal disorders in a population of acquired immune deficiency syndrome (AIDS) patients with cerebral toxoplasmosis. Of 240 AIDS patients evaluated in the 1985-1994 period, 50 of them were diagnosed to have cerebral toxoplasmosis on the basis of the following criteria: occurrence of specific antibodies, computed tomography and/or magnetic resonance imaging (MRI), and regression of the symptoms after specific therapy. Three of 50 (6%) had hemichoreoathetosis. In the first case, the disorder began as a dyskinesia of the left hand that subsequently spread to the whole ipsilateral arm and assumed the features of choreic athetotic movements. The other two cases were characterized by left hemisomatic distal choreic movements. Therapy with pyrimethamine and sulfadiazine led to a complete recovery of the extrapyramidal signs in two cases and to improvement in the third. According to our observations, the onset of these movement disorders could not be related to the dimension of the lesion or to the edema, but to a specific localization in subthalamic nucleus, in subthalamic/pallidal, and pallidal/thalamic pathways. MRI seems the elective tool to perform a more accurate study of the anatomic areas involved in this pathway and to verify their integrity. Cerebral toxoplasmosis in AIDS can be considered as a new etiopathogenic cause of choreoathetosis.

Polymerase chain reaction for non-invasive diagnosis of brain mass lesions caused by Mycobacterium tuberculosis: report of five cases in human immunodeficiency virus-positive subjects

To investigate whether the polymerase chain reaction (PCR) on the IS6110 sequence of Mycobacterium tuberculosis could permit the early and non-invasive diagnosis of tuberculous brain lesions without meningeal involvement in acquired immunodeficiency virus patients, we examined retrospective cerebrospinal fluid (CSF) samples from five patients diagnosed as having cerebral lesions caused by M. tuberculosis. M. tuberculosis deoxyribonucleic acid was detected in CSF samples obtained from each of the patients studied, but in none of the controls. The PCR results coincided with M. tuberculosis isolation from CSF in two patients. In an additional two subjects, culture for M. tuberculosis on CSF was negative, and the diagnosis of central nervous system tuberculosis was achieved by response to specific therapy. In the last patient the PCR result on CSF was confirmed by isolation of M. tuberculosis from brain biopsy. Interestingly, in this patient the CSF did not yield M. tuberculosis isolation when cultured. The data show the value of PCR as a potentially useful approach for the early and rapid diagnosis of cerebral tuberculosis even without meningitis.

Evaluation of a western blot serum test for the diagnosis of Mycobacterium tuberculosis infection

This study was designed to evaluate the possibility of monitoring Mycobacterium tuberculosis infection using a serological assay. A discriminant score comprising antigen fractions of 38, 28, 24 and 19 kDa, identified in western blots using the Mycobacterium bovis bacille Calmette-Guérin (BCG) A60 antigen complex was established in a sample of 57 purified protein derivative (PPD)-negative and 47 PPD-positive individuals. It was then tested in a group of 140 subjects undergoing BCG vaccination as a model of tuberculosis complex infection and in a group of human immunodeficiency virus (HIV)-infected individuals as a model of cell-mediated immunodeficiency-related risk of tuberculosis. The discriminant score identified 57 out of 57 (100%) PPD-positives and none (0%) of the 47 PPD-negatives. In the BCG vaccinated subjects, 1.4% tested positive before vaccination and 90% after vaccination. In the HIV-positive subjects, 90% of the PPD-positive and 5% of the PPD-negative subjects had a positive score. This study suggests that the western blot discriminant score is an accurate test to survey M. tuberculosis infection in serum samples.

Drug injection in jugular veins: a new risk factor for vascular diseases in HIV-infected patients? A case report

The authors describe a rare case of diffused thrombosis of the superficial veins in the whole body and periphlebitis with perivascular abscesses in an human immunodeficiency virus (HIV)-infected drug abuser who was using neck veins to inject cocaine and heroin. In addition the patient presented oral candidiasis, hepatitis C virus infection, bronchopneumonitis, and endocarditis of the tricuspid valve with valvular failure. The conditions of the patient needed repeated vascular catheterizations for therapy administration. Similar pathologies, in HIV-infected patients, highly increase the risk of opportunistic infections, especially in the encephalic territory; in addition the need for vascular catheterizations represents a further risk factor for bacterial infections.

Intestinal microsporidiosis in AIDS patients with diarrhoeal illness in Apulia (south Italy)

Microsporidia are intracellular parasitic protozoa very common in immunocompromised patients in many parts of the world. There is a scarcity of data on the prevalence of these parasites in Italy. In this study we examined stool samples of 56 HIV+ patients with diarrhoea to find microsporidial spores, using the light microscopy Ryan modified trichrome stain. Microsporidia were found in one out of 56 patients, who was Cryptosporidium coinfected. Intestinal microsporidiosis seems to be less frequent in AIDS patients from Italy than in those from other countries.

Efficacy of itraconazole in treating AIDS-associated infections due to Candida krusei

Candida krusei is an emerging pathogen, both in HIV negative immunocompromised patients and in HIV seropositive patients. Its onset appears to be due, at least in part, to the use of fluconazole. In HIV positive patients, a long term prophylactic use of fluconazole may select some less pathogenic Candida species, as C. krusei, that may determine persistent oral candidiasis and emerge as systemic pathogen. Itraconazole appears efficacious in treating AIDS-associated C. krusei infections.

P24 antigen detection, viral isolation, DNA-PCR and in vitro antibody production for the diagnosis of HIV-1 latent infection in heterosexual women at high risk for HIV-1 infection

INTRODUCTION

The report of the existence of at-risk seronegative subjects, latently infected with HIV-1 and producing "in vitro" HIV-1 specific antibodies, prompted the authors to evaluate extensively twenty-five heterosexual HIV-1 seronegative women at high risk for HIV-1 infection.

MATERIAL AND METHODS

The capability of peripheral blood mononuclear cells from such subjects to produce "in vitro" HIV-1 specific antibodies after pokeweed-mitogen stimulation, was studied. Silent HIV-1 infection was investigated by HIV-1 DNA PCR, viral isolation and serum p24 Ag detection at entry and after 6 and 12 months.

RESULTS

Three seroconversions took place within 12 months, but no HIV-1 infections were found in the absence of detectable serum anti HIV-1 antibodies, even in subjects who apparently produced such antibodies in vitro. The antibodies produced in vitro by the seronegative women studied appeared of narrow specificity, reacting mainly with gp 160/120 envelope glycoproteins.

CONCLUSIONS

A strong concordance was found between the serological status and the other markers for HIV-1 infection, suggesting that the phenomenon of HIV-1 "latent infection" is a very rare event, if it occurs at all. Seronegative women sexually exposed to the virus may produce in vitro anti HIV-1 antibodies of narrow specificity in the absence of other signs of infection and this phenomenon might be related to an anamnestic response to the virus.

Drug resistance of Mycobacterium tuberculosis strains isolated from HIV-infected Italian patients: preliminary report from a multicentric study. The Italian Tuberculosis Drug Resistance Study Group

A multicentric prospective study started in March '93 to describe both initial and acquired resistance of Mycobacterium Tuberculosis in Italian HIV+ patients (pts.) to first line drugs: Rifampin (R), Isoniazid (I), Pyrazinamide (P), Ethambutol (E), Streptomycin (S). All tuberculosis (TB) cases diagnosed in HIV+ patients (pts.) were included, along with clinical-anamnestical data. Drug-susceptibility tests were performed centrally. Preliminary results indicate an overall low frequency of TB resistance to first line drugs: R = 2%, P = 4%, S = 9%, I/E = none. However, a relevant nosocomial outbreak of multiple drug resistant (DR) TB was detected. This finding, along with some previous Italian reports of DR-TB clusters, may herald a further spread of DR-TB. Surveillance, therefore, is mandatory in Italy from now on.

Cyclospora in AIDS patients: not always an agent of diarrhoic syndrome

The present study reports the clinical features of two AIDS patients infected by Cyclospora. According to our observations, Cyclospora in AIDS can be responsible both for gastroenteritis and for asymptomatic infections with spontaneous rapid clearance. In addition, and undiagnosed circulation of this agent in Italy could be hypothesized: neither patient had a past history of foreign travel. These are the first two cases in AIDS described in Italy.

Chronic cryptococcal meningitis in an intravenous drug addict without evidence of infection by HIV-1,2 in southern Italy

Before the emergence of AIDS, extrapulmonary cryptococcosis was very rare. By contrast, meningeal cryptococcosis is a very common opportunistic infection in AIDS patients. We report an intravenous drug addict with cryptococcal meningitis, who was not infected with HIV and had no apparent predisposing conditions. This case, as those elsewhere described, supports the potential existence of viral agents, other than HIV-1,2 capable of encouraging the occurrence of unusual infections as have emerged during the AIDS pandemic.

The biological phenotype of HIV-1 is usually retained during and after sexual transmission

The biological phenotype of HIV-1 isolates from 21 subjects with primary HIV-1 infection was determined in primary lymphocytes and monocyte-derived macrophages as well as in three T-cell lines (MT-2, HUT78, and C8166). Seven isolates (33%) replicated on at least one cell line and were classified as rapid/high (n = 6) or intermediate (n = 1), while 14 isolates (67%) did not replicate in cell lines and were classified as slow/low. All isolates replicated in primary monocyte-derived macrophage cultures. Studies on 10 pairs consisting of index case and seroconverting sexual partner showed that the biological phenotype of HIV-1 was unchanged in nine transmissions, including 5 pairs where a rapid/high virus was transmitted. Most individuals (5 of 6) infected by a rapid/high virus retained this phenotype after seroconversion. These individuals also had significantly lower CD4 lymphocyte counts 1-3 years after infection. Thus, in contrast to what has been suggested by others, we found that HIV-1 variants with rapid/high phenotype were usually not suppressed, neither during sexual transmission nor after seroconversion in the new host. These findings have important implications for the understanding of HIV-1 transmission and pathogenesis as well as for vaccine design.

Apparent selection against transmission of zidovudine-resistant human immunodeficiency virus type 1 variants

The sexual transmission of zidovudine-resistant human immunodeficiency virus type 1 (HIV-1) variants was investigated in 5 donor-recipient pairs in which all donors and none of the recipients had received zidovudine treatment. The virus isolates were tested for sensitivity to zidovudine (IC50) in vitro using blood donor lymphocytes. A region of the HIV-1 pol gene was also directly sequenced by a solid-phase sequencing method. Four donors were shown to have zidovudine-resistant HIV-1 variants. Two of these patients had a single mutation (Thr215-->Tyr), and 2 had a double mutation (Met41-->Leu and Thr215-->Tyr) that previously has been shown to confer zidovudine resistance. Zidovudine-resistant virus was found in only 1 of the 4 recipients, which indicates that zidovudine-resistant HIV-1 variants may be selected against during transmission. Thus, the transmission of zidovudine-resistant HIV-1 variants is a complex process that will require consideration whenever zidovudine treatment is initiated in persons who may have been infected by resistant variants.

Possible significance of antibodies to Legionella pneumophila in HIV-1 infected patients with acute respiratory illness

Eighty-six serum samples from 52 HIV-1 infected patients with complicating pneumonia illness were assayed for the presence of antibodies to Legionella pneumophila. In 25 of these patients Pneumocystic carinii has been previously diagnosed. Among all patients investigated only 4 had antibodies to L. pneumophila of significant titer of 128. In one patient L. pneumophila was demonstrated coexisting with P. carinii. Despite of a small proportion of patients with a significant titer of antibodies against L. pneumophila, the presence of this microorganism should be carefully investigated in AIDS patients with complicating pneumonia especially when the aetiological diagnosis is not defined; the reason is to improve the therapeutic treatment.

Early abnormalities of the antibody response against Mycobacterium tuberculosis in human immunodeficiency virus infection

Among human immunodeficiency virus (HIV)-infected persons, those who react against purified protein derivative (PPD) have higher risk of tuberculosis. Since PPD testing has limited predictive power in HIV-positive populations, new markers of antituberculous immunity were sought by analyzing antibodies to Mycobacterium tuberculosis antigens (PPD and its fraction A60) in 102 HIV-positive subjects, some PPD-positive and some PPD-negative, and in 23 HIV-positive tuberculosis patients. ELISA and Western blotting were used. Forty HIV-negative healthy subjects and 40 HIV-negative tuberculosis patients were evaluated as controls. While all those HIV-negative and PPD-positive had IgG antibodies recognizing the 38-, 28-, and 19-kDa M. tuberculosis antigens, only 26% of those HIV-positive and PPD-positive (all with < 400 CD4+ cells/mm3) and none of the HIV-positive tuberculosis patients recognized them, indicating that the lack of IgG against those antigens, in the presence of a specific IgM response, is a marker of immunodeficiency.

Detection of human T lymphotropic virus type II/b in human immunodeficiency virus type 1-coinfected persons in southeastern Italy

A preliminary screening of 511 persons at risk for AIDS living in southeastern Italy disclosed 20 cases of seroreactivity to human T lymphotropic viruses (HTLV). To verify and type the HTLV infection among these subjects, confirmatory serologic tests, polymerase chain reaction (PCR), and virus culture were done. No evidence of HTLV-I infection was found. HTLV-II infection was confirmed in 8 cases by HTLV-specific, synthetic peptide EIAs and PCR on uncultured cells; restriction analysis of the PCR-amplified env regions revealed the presence of HTLV-II/b strains in all 8 cases. Four sera were nontypeable by EIA. The finding of such indeterminate reactivities in a geographic area in which HTLV variants were previously described indicates the need for more extensive surveys among the healthy population. HTLV-II was isolated in 5 cases, and virus isolation was mostly dependent on the presence of an actively replicating human immunodeficiency virus type 1 in culture.

Current problems in treating tuberculosis in Italian HIV-infected patients

31 Italian HIV-infected patients with newly diagnosed tuberculosis (TB) were reviewed to verify the effectiveness of the most common antituberculosis drugs. The patients were mostly intravenous drug addicts (90%), and 14 (45%) had recently been in prison. 5 patients (16%) had pulmonary TB, 15 (48%) had both pulmonary and extrapulmonary involvement, and 11 (30%) had extrapulmonary disease alone. 6 patients received the association of HRZ, and a 4-drug association including ethambutol was given to an additional 7 patients. The remaining 18 patients were administered the association of HRE. Response to therapy was good in 13 patients (42%), and lacking or delayed in 18 patients (58%). Treatment failure was partly related to the increased occurrence in our area of Mycobacterium tuberculosis strains resistant to the first-line anti-tuberculosis drugs. These observations, along with the need of a faster response to therapy than that currently obtained for TB in AIDS and in view of epidemiological effects, should prompt the definition of alternative therapeutic and prophylactic regimens.

Neutralizing antibodies to recombinant alpha-interferon and response to therapy in chronic hepatitis C virus infection

Forty-seven patients with chronic hepatitis C were treated with recombinant interferon alpha-2a (rIFN alpha 2a) given subcutaneously in a standard dose of 3 MU thrice weekly for 12 months. Stored baseline sera and monthly samples during treatment were assayed for anti-interferon neutralizing antibodies using the antiviral neutralization bioassay against 5 IU of rIFN alpha 2a. During therapy, 15 of 47 patients (31.9%) developed detectable levels of neutralizing antibodies within 2-8 months after starting treatment. After 12 months of therapy, 26 of 32 antibody-negative patients (81.3%) showed normalization or marked reduction of ALT levels compared to 4 of 15 (26.6%) who developed anti-IFN neutralizing antibodies (p = 0.0009). Four patients demonstrated antiviral response during treatment even in the presence of low levels or late occurrence of neutralizing antibodies. Six of the seven patients who had disease reactivation after an initial response developed high titers of neutralizing antibodies. Our results suggest that reactivation of chronic hepatitis C before completion of therapy seems to be an obvious consequence of anti-IFN neutralizing antibody formation.

Man-to-woman sexual transmission of HIV: longitudinal study of 343 steady partners of infected men

To study incidence and risk factors of heterosexually transmitted HIV infection, we followed a cohort of 343 seronegative women, stable, monogamous partners of infected men whose only risk of acquiring HIV was sexual exposure to the infected partner. Nineteen seroconversions occurred in 529.6 person years (py) of observation, yielding an incidence rate of 3.6 per 100 py. The incidence rate was 7.2 per 100 py among women who did not always use or never used condoms and 1.1 among those who always used them [relative risk (RR) 6.6, 95% confidence interval (CI) 1.9-21.9]. Anal sex was associated with a risk increase in only those women not always using condoms (RR 1.4, 95% CI 0.4-4.8). No seroconversions were observed among 22 women using oral contraceptives. One of the women using intrauterine devices seroconverted. In couples who did not always use condoms, seroconversions occurred more frequently in partners of men with symptomatic diseases, with a low CD4+ cell number (< 400 per mm3) or with a detectable p24 antigen. In couples not always using condoms and where the man had a low CD4+ cell count, the joint presence of blood viral antigens and AIDS symptoms conditioned a fivefold increased risk of seroconversion of the woman (RR 5.4, CI 1.4-20.3). At multivariate analysis, women with longer relationships (> or = 1 year) showed a lower risk of seroconversion (RR 0.3, CI 0.1-0.8), and those partners of men positive for p24 antigen in serum had an increased risk of seroconversion (RR = 4.0, CI 0.1-0.8).

A simple method to detect HIV-1 protein specificity of IgG intrathecal synthesis in HIV-1 infection

There is currently no simple method to detect the antigen specificity of anti-HIV-1 IgG intrathecal synthesis (IS). Fifty-seven pairs of serum and corresponding CSF from 29 HIV-1 seropositive patients were adjusted to an identical concentration of total IgG and tested by a commercial HIV-1 Western Blot (WB) assay. IgG IS to a given HIV-1 protein was demonstrated when the corresponding band was present in CSF but absent or significantly less represented in serum. A total anti-HIV-1 IS was defined as the presence of an IS to one or more HIV-1 antigens. Our WB analysis of CSF and serum, compared with conventional mathematical formulas, showed a higher sensitivity in demonstrating anti-HIV-1 IgG IS. Moreover, the method disclosed which HIV-1 proteins represent the target of IgG IS. This procedure is easy to perform and therefore may represent a valuable tool to study central nervous system (CNS) involvement by HIV-1 during different stages of infection.

Prevalence of cryptosporidiosis in HIV-infected patients with diarrhoeal illness

Protozoans of the genus Cryptosporidium may cause serious diarrhoeal illness in immunocompromised hosts and especially in HIV-infected patients. In this study we have evaluated the frequency of Cryptosporidium in stools of 51 HIV-infected patients with diarrhoea. Laboratory diagnosis of cryptosporidiosis was performed of faecal samples concentrated by a formalin-ether sedimentation technique and stained by a modified cold Ziehl-Neelsen method. Results demonstrated that 17 (33.3%) of these patients were infected with Cryptosporidium. Moreover, Cryptosporidium infection was the first clinical marker of AIDS in 7 cases. Our data show that the prevalence of this parasitosis in HIV-infected people seems to be higher in our region (Apulia, South Italy), compared to other areas of the world.

Preliminary data on the establishment of permanent cell lines continuously producing HIV-1: factors affecting the transmissibility and adaptability of "wild" HIV-1 isolates

This study examines some technical aspects of the transmission to and permanent adaptability in continuous cell lines of wild HIV-1 isolates. Three cell systems (the lymphocytic cell lines Molt-3 and H-9 and the monocytoid cell line U-937) and two transmission protocols (cell to cell and cell-free) were used. Two different replicative behaviours were observed among isolates efficiently transmitted: a) transmissibility but not adaptability (consisting in a limited length of viral replication); aa) transmissibility and adaptability (consisting in a stable and long term virus production). The second type of replication was confined to viruses from patients with severe immunodeficiency. Technical and viral factors can affect the rate of transmissibility and adaptability: the modality of infection (cell to cell transmission appeared to be the most efficient) and the tropism of the virus (some viruses could infect only one T cell line).

Correlation between seroreactivity to HIV-1 V3 loop peptides and male-to-female heterosexual transmission

OBJECTIVE

To evaluate the correlation between seroreactivity to peptides corresponding to the V3 loop of the major envelope glycoprotein from different HIV-1 strains and the risk of heterosexual HIV-1 transmission.

METHODS

Sera from 39 infected individuals (16 transmitters and 23 non-transmitters) were tested for reactivity against synthetic peptides representing sequences of the V3 loop apex from HIV-1 strains MN, SC, WMJ2, RF and IIIB.

RESULTS

A skewed distribution in seroreactivity to RF and IIIB peptides was observed between the two groups: reactivity was more prevalent in sera from non-transmitting than from transmitting individuals. Reactivity to the MN, SC and WMJ2 peptides was very frequent and there were no differences between the two groups.

CONCLUSION

These data suggest that antibodies reactive with a larger set of V3 apex peptides (i.e., cross-reactive antibodies) could play a role in the prevention of heterosexual transmission.

Zidovudine prophylaxis after accidental exposure to HIV: the Italian experience. The Italian Study Group on Occupational Risk of HIV Infection

OBJECTIVES

To evaluate the use of zidovudine prophylaxis in HIV-exposed health-care workers (HCW) in Italy and to determine its short-term toxicity.

DESIGN

Longitudinal, open study with retrospective and prospective collection of data.

SETTING

All Italian clinical centres that care for HIV-infected patients and are licensed by the Ministry of Health to dispense zidovudine and 30 hospitals participating in the Italian Multicentre Study on Occupational Risk of HIV Infection.

STUDY POPULATION

HCW and other individuals who accepted zidovudine prophylaxis after accidental exposure to HIV.

RESULTS

Data were collected for 224 HIV-exposed individuals until 30 June 1991. An increase in zidovudine prophylaxis was observed. All but 10 subjects received 1000-1250 mg zidovudine per day. Anaemia (five cases), neutropenia (one case) and an increase in serum alanine aminotransferase levels (two cases) were the only haematochemical side-effects observed; none of the subjects ceased prophylaxis because of side-effects. More than 50% of subjects had constitutional reactions; as a result, prophylaxis was stopped by 29 patients. These adverse effects began within 10 days of prophylaxis; all resolved after prophylaxis was stopped. No HIV-antibody seroconversions were observed after a mean follow-up of 8 months.

CONCLUSIONS

Zidovudine prophylaxis has become a feature of the management of occupational exposures to HIV in health-care settings; short-term toxicity is mild, dose-related and reversible. Further studies are needed to assess the risk of long-term sequelae.

[Ogilvie's syndrome: clinical reality or nosographic error?]

The authors report their experience in the management of Ogilvie's syndrome, a rare form of large bowel acute pseudo-obstruction. The study includes fifteen cases of the disease. There were ten males and five female, with a mean age of sixty-two years (range 45-92). Three patients were only treated with medical and conservative measures, one with unsuccessful colonoscopy and twelve (two with colonic perforation) underwent laparotomy. The surgical procedures performed were tube cecostomy (40%), colonic resection with primary anastomosis (27%) and exploratory laparotomy with decompression (13%). The overall morbidity and mortality rate were respectively 0 and 13%. Our epidemiological, clinical and therapeutic results are similar to those reported in the international literature. The pathophysiology of the syndrome is still unknown. It can be "idiopathic" or can complicate other diseases or surgical procedures (urological and gynaecological procedures mostly). Plain abdominal roentgenogram is the most useful diagnostic test, but colonoscopy may be an alternative diagnostic (and therapeutic) weapon. Conservative treatment is the method of choice but when the cecal diameter is more than 12 cm. (impending perforation), when the colon is perforated or when medical measures are unsuccessful, surgical procedure is compulsory. The age of the patient, cecal size, delay in colonic decompression are the most important prognostic factors. Even with a proper management, the prognosis is severe and the mortality rate is high (3-50%).

Anti-nef antibodies and other predictors of disease progression in HIV-1 seropositive injecting drug users

A cross-sectional and retrospective longitudinal study has been conducted in three Italian infectious disease centres to evaluate the role of anti-nef antibodies and other markers (HIV-1 p24 antigen, p24 Ag; Beta 2-microglobulin, B2-M; and number of CD4+ lymphocytes) as predictors of disease progression in HIV seropositive injecting drug users (IDUs). The selected patients were: 1) HIV-seropositive IDUs in different stages of HIV infection; 2) HIV-seropositive IDUs who had developed AIDS, from whom serial serum samples were available during the asymptomatic stage, and 3) HIV seropositive IDUs who remained asymptomatic through a follow-up period of the same duration as the patients who developed AIDS. Absence of anti-nef antibodies was associated with symptomatic HIV infection. A significant association between the absence of anti-nef antibodies, the presence of p24 Ag, high levels of B2-M, a number of CD4+ lymphocytes less than 500/ml at first visit and disease progression was found. Subjects who were persistently positive for antibody to nef were less likely to develop AIDS than those who were transiently or persistently negative. This difference was statistically significant (p = 0.03). The results of this study show that absence or disappearance of anti-nef antibodies may be used as predictor of disease evolution in HIV seropositive IDUs. This study also confirms the usefulness of other markers, such as p24 Ag, B2-M and number of CD4+ lymphocytes previously shown to be predictive of rapid disease progression for predicting the course of HIV seropositive IDUs.

HIV-1 isolation from small amounts of whole blood: a technical evaluation

We have evaluated a simple and sensitive culture technique for isolation of Human Immunodeficiency Virus Type-1 (HIV-1) from small amounts of whole blood. Data shown in the paper demonstrate that: 1) cell cultures from small amounts of heparinized whole blood (HWB) allow a high isolation rate in infected subjects at all stages of diseases; 2) among asymptomatic subjects the HIV-1 isolation rate is increased in cell cultures from HWB, with respect to cell cultures from peripheral blood mononuclear cells; 3) cultural results from HWB are not influenced by the presence of detectable serum p24 antigen, but a good correlation was found with the titre of anti p24 antibodies in serum; 4) continuous cell lines (such as Molt-3 cells) instead of peripheral blood mononuclear cells can be used, obtaining good results, for HIV-1 isolation from HWB; 5) frozen samples of HWB can be used in cell cultures for HIV-1 isolation; 6) the type of anticoagulant (Heparin or EDTA) used for the collection of blood does not influence viral replication in cell cultures from whole blood; 7) viral isolation from HWB is highly sensitive; amounts so small as five microliters of whole blood are sufficient, in some cases, to obtain viral replication in cell cultures; 8) the minimal dose of HWB sufficient to infect cell cultures (HWB M.D.I.) varied among different patients. Although this work failed to establish a correlation between this parameter and the clinical and immunological status of patients, it is conceivable that HWB M.D.I. could give information about viral load in blood and have a prognostic significance; 9) the HWB M.D.I. rise in patients treated with Zidovudine, suggesting that this method could be employed in the virological evaluation of trials with antiretroviral drugs.

Lack of HBV and HDV replicative activity in HBsAg-positive intravenous drug addicts with immune deficiency due to HIV

The effects of HIV infection on HBV and HDV replication and liver damage were evaluated by comparing the findings from 48 anti-HIV-positive HBsAg chronic carriers with those from 22 matched anti-HIV-negative subjects. The state of HBV/HDV infection was also related to the degree of immunodeficiency of the anti-HIV-positive patients. Most patients were intravenous drug addicts (IVDA) (84.2%); male homosexuals represented only a small proportion (7.1%). Serum HBV-DNA was detected more frequently in anti-HIV-negative than in anti-HIV-positive patients (50% vs. 35%) despite evidence of HDV replication in the anti-HIV-negative group (P = 0.02). Seroconversion from ongoing to inactive HBV infection occurred in 45% of anti-HIV-negative patients as well as in 23% of anti-HIV-positive patients (P = ns). The difference in severity of liver damage between the two groups was not statistically significant (P = 0.84). Furthermore, in the anti-HIV-positive subjects, HBV and/or HDV activity was detected in 63% of patients with mild immunodeficiency (CDC groups II and III with a total CD4 count greater than 400/mm3) and also in 75% of ARC-AIDS patients (CDC groups IV A-IV C) (P = ns). Severe hepatic disease occurred in subjects with CD4 counts above or below 400/mm3 (13 vs. 6, respectively). In conclusion, the data do not demonstrate that HBV or HDV infections are modified by HIV. The epidemiological background of the patients investigated and the extensive spread of hepatitis viruses in Italy before the appearance of HIV may account for the lack of relationship between HIV and HBV/HDV infections.

[Isolation of human immunodeficiency virus (HIV) from whole blood]

The authors describe a simple and sensitive technique for HIV isolation from small amounts of heparinized whole blood. This method demonstrated a high efficiency in detecting HIV at all stages of disease and appeared more sensitive with respect to viral isolation from peripheral blood mononuclear cells. Although further studies are needed to better understand the biological significance of a positive cultural result obtained by this method, HIV isolation from whole blood can be routinely employed, especially when small amounts of blood are available.