The mortality and pathology of HIV infection in a west African city

Infections and other causes of death in HIV-infected children in Africa

The human immunodeficiency virus (HIV) pandemic has dramatically reversed improvements in infant mortality and child survival in sub-Saharan Africa. However, accurate information on the specific causes of HIV-related morbidity and mortality arising from vertical transmission is infrequent and is constrained in resource-poor settings by infrastructure and local access to health care. Such knowledge is essential to improve clinical management of HIV-infected children in Africa. In this review, a global overview of the clinical aspects of HIV infection in children is given. Factors influencing HIV disease progression, morbidity and mortality are discussed from studies on a cohort of HIV-infected children that were followed at an orphanage in Nairobi between 1999 and 2001. These parameters are contrasted with available data on HIV-infected children residing in community settings in Africa.

Initiating highly active antiretroviral therapy in sub-Saharan Africa: an assessment of the revised World Health Organization scaling-up guidelines

OBJECTIVES

To assess the utility of the 2003 revised World Health Organization (WHO) criteria [initiating highly active antiretroviral therapy (HAART) in stage IV, in stage III plus CD4 cell count < 350 x 10(6) cells/l, or in stage I or II plus CD4 cell count < 200 x 10 cells/l] relative to other scenarios of HAART initiation.

METHODS

Progression to AIDS and death in 292 patients taking HAART and 974 not taking HAART in a South African institution in 1992-2001, stratifying patients by baseline CD4 cell count and WHO stage.

RESULTS

HAART was associated with decreased AIDS [adjusted rate ratio [ARR], 0.16; 95% confidence interval (CI), 0.08-0.31) and death (ARR, 0.10; 95% CI, 0.06-0.18). Benefit of HAART was significant across all WHO stages plus CD4 cell counts. The greatest number of deaths averted was in stages IV [74.0/100 patient-years (PY); 95% CI, 50.2-84.5) and III (32.8/100 PY; 95% CI, 22.4-40.9). AIDS cases averted in stage III (22.0/100 PY; 95% CI, 6.1-26.9) were higher than in stage I and II with CD4 cell count < 200 x 10(6) cells/l (8.9/100 PY 95% CI, 5.6-13.3). Treatment initiation for symptomatic disease resulted in greater benefits than using any CD4 cell thresholds. Application of WHO criteria increased the treatment-eligible proportion from 44.5% to 56.7% (P < 0.05) but did not prevent more death (P > 0.05) than treating symptomatic disease.

CONCLUSION

Implementation of the revised WHO guidelines in sub-Saharan Africa may result in a significantly increased number of individuals eligible for treatment but would not be as effective a strategy for preventing death as treating symptomatic disease.

Épidémie de sida en Afrique subsaharienne

Knowledge useful to the fight against HIV/AIDS in sub-Saharan Africa cannot be extrapolated to those coming from industrialized countries. The aim of this article is to review specificities of the African epidemy, in terms of epidiomolgy, natural history, validated therapeutic interventions, and unexplored questions. Far from being without effective tools and research tracks to fight against this plague which decimates a continent, one is above all confronted with a deficit of both mobilization and means.

Tuberculosis in HIV-infected patients: a comprehensive review

The incidence of tuberculosis (TB) is currently increasing in HIV-infected patients living in Africa and Asia, where TB endemicity is high, reflecting the susceptibility of this group of patients to mycobacteria belonging to the TB group. In this population, extension of multiple resistance to anti-tuberculous drugs is also a matter of anxiety. HIV-induced immunosuppression modifies the clinical presentation of TB, resulting in atypical signs and symptoms, and more frequent extrapulmonary dissemination. The treatment of TB is also more difficult to manage in HIV-infected patients, particularly with regard to pharmacological interactions secondary to inhibition or induction of cytochrome P450 enzymes by protease inhibitors with rifampicin or rifabutin, respectively. Finally, immune restoration induced by highly active anti-retroviral therapy (HAART) in developed countries may be responsible for a paradoxical worsening of TB manifestations.

Factors associated with clinical progression in HIV-2 infected-patients: the French ANRS cohort

OBJECTIVES

To identify factors associated with clinical progression in HIV-2 infected patients.

DESIGN

French prospective cohort initiated in 1994.

METHODS

Follow-up data are collected twice a year; viral load is assessed once a year by cellular viraemia, quantitative proviral DNA and plasma RNA. A Cox proportional-hazards model was used for studying baseline factors associated with clinical progression.

RESULTS

By December 2001, 217 patients had been enrolled. At inclusion, 80%, 6% and 14% were Centers for Disease Control and Prevention (CDC) group A, B and C, respectively. Median CD4 cell count was 436 x 10(6)/l. In the 48% of positive specimens, the median plasma RNA titre was 3.0 log10 copies/ml. Mean follow-up of the 179 patients seen at least twice was 34.4 months. Of these 13 died and nine progressed to group C. Ninety-three (52%) received antiretroviral therapy during a mean of 33 months, including a protease inhibitor in 48%. The probability of remaining AIDS-free was 97% and 95% at 1 and 3 years, respectively. Independent variables associated with clinical progression were age > or = 40 years [hazard ratio (HR), 11; 95% confidence interval (CI), 1.4-91.8; P = 0.03] and plasma RNA (HR, 2.5 per additional log10 copies/ml; 95% CI, 1.3-4.7, P < 0.01). Prior group B symptoms and CD4 cell count < 200 x 10(6)/l were associated with progression to AIDS. AIDS and plasma RNA were predictive of death.

CONCLUSION

Considering the limited progression rate of HIV-2 infection, combined antiretroviral therapy should be discussed in patients with high plasma RNA titres, which threshold value remains to be defined. It is recommended in case of AIDS, CDC group B symptoms or CD4 cell count < 200 x 10(6)/l.

Growth, Morbidity, and Mortality in a Cohort of Institutionalized HIV-1???Infected African Children

OBJECTIVE

As a result of the HIV epidemic in Africa, much debate exists on whether institutionalized compared with community-based care provides optimum management of infected children. Previous reports calculated 89% mortality by age 3 years among outpatients in Malawi. No similar data are available for infected children in institutionalized care. We characterized patterns of morbidity and mortality among HIV-1-infected children residing at an orphanage in Nairobi.

METHODS

Medical records for 174 children followed over 5 years were reviewed. Mortality was analyzed by Kaplan-Meier methods with adjustment to account for survival in the community before admission. Anthropometric indices were calculated to include mean z scores for weight for length and length for age. Low indices reflected wasting and stunting. Opportunistic infections were documented.

RESULTS

Of 174 children, 64 had died. Survival was 70% at age 3 years. Morbidity included recurrent respiratory tract infections, gastroenteritis, parotitis, and lymphoid interstitial pneumonitis. No new cases of tuberculosis disease were noted after admission. Mean z scores for length for age suggested overall stunting (z = -1.65). Wasting was not observed (z = -0.39).

CONCLUSION

The optimal form of care for HIV-infected children in resource-poor settings may be the development of similar homes. Absence of tuberculosis disease in long-standing residents may have contributed to improved survival. Stunting in the absence of wasting implied that growth was compromised by opportunistic infections and other cofactors.

HIV infection and chronic chest disease as risk factors for bacterial pneumonia: a case-control study

OBJECTIVES

To investigate risk factors for severe acute pneumonia in South African gold miners.

DESIGN AND METHODS

An inclusive case-control study drawn from a predefined cohort of 4762 miners of known HIV status. Cases were defined by hospital admission meeting the clinical and radiological case definitions for pneumonia during 1998. Controls were randomly selected from the starting cohort. Considered risk factors were: HIV infection, smoking, age, occupation, previous tuberculosis, and chronic premorbid chest disease caused by post-tuberculous lung disease or silicosis (International Labour Office grades 1/0 and above) defined from routine screening radiographs taken before the start of the study.

RESULTS

There were 109 cases and 400 controls. HIV infection [odds ratio (OR) 31.6], previous tuberculosis (OR 2.4), and an abnormal premorbid radiograph (OR 2.8) were each significantly more prevalent in cases than controls, whereas other variables were not. On multivariate analysis, HIV infection [OR 30.7, 95% confidence interval (CI) 12.1-78.1] and an abnormal premorbid radiograph (OR 2.3, 95% CI 1.1-4.8) remained significant risk factors. Median CD4 cell counts in HIV-positive cases with and without abnormal premorbid radiographs were 185 and 162 x 106/l, making confounding between chronic chest disease and the extent of immunocompromise an unlikely explanation for this association.

CONCLUSION

HIV infection and an abnormal premorbid chest radiograph are both strong risk factors for pneumonia in miners. Pre-existing chronic chest disease may be an important risk factor for HIV-associated pneumonia in other populations, and if so, is an additional indication for considering antibiotic prophylaxis in HIV-positive individuals.

Productive HIV-2 infection in the brain is restricted to macrophages/microglia

OBJECTIVES

HIV-2 can use a broader range of co-receptors than HIV-1 in vitro, and is less dependent on CD4 for infection. The aim of this study was to detect productive HIV-2 infection in the brain and investigate whether HIV-2 has an expanded tropism for brain cells in vivo, in comparison with HIV-1, which productively infects macrophages/microglia.

DESIGN

Brain samples taken at autopsy from eight patients who died from AIDS, six HIV-2 and two HIV-1/HIV-2 dually seropositive, with HIV encephalitis (HIVE), collected in Abidjan, Côte d'Ivoire in 1991, were examined for the presence and localization of productive HIV-2 infection.

METHODS

Using immunohistochemistry, the presence of HIV-2 p26 in formalin-fixed, wax-embedded brain tissue sections was investigated. Double-staining with glial fibrillary acidic protein (GFAP), CD45- and CD68-specific antibodies was performed to identify infected cell types.

RESULTS

HIV-2 p26 was detected in brain tissue from four of the HIV-2 cases and one of the dually infected individuals. The productively infected cells were either microglia or infiltrating macrophages.

CONCLUSIONS

The productively infected cells in the brains of HIV-2 infected individuals are macrophages/microglia. No evidence was found for productive infection of astrocytes, neurons or oligodendrocytes. Thus, the broader in vitro cell tropism, promiscuous coreceptor usage and relative independence of CD4 by HIV-2 compared to HIV-1 does not broaden its range of target cells in the brain.

Broad spectrum of coreceptor usage and rapid disease progression in HIV-1-infected individuals from Central African Republic

To study the progression of HIV-1 infection and coreceptor usages in Central African Republic, clinical data, plasma viral load, and coreceptor usage of sequential HIV-1 isolates were analyzed in a seroincident prospective cohort (PRIMOCA). Twenty-three HIV-1 infected individuals from the Central African Armed Forces were followed from 1995 to 2000. Viruses were isolated from 17 patients at various time points after seroconversion and their coreceptor usage was examined using GHOST cells expressing CD4 and one of the HIV-1 chemokine coreceptors CCR5, CXCR4, BOB/GPR15, and Bonzo/STRL33/CXCR6. Eleven patients died from AIDS. Eight of them died between 2 and 5 years after seroconversion, after a brief symptomatic stage. Patients who rapidly progressed to AIDS and death displayed the highest viral loads after seroconversion. All isolates obtained soon after seroconversion used CCR5, albeit, in some cases, CXCR4, BOB, or Bonzo were also used. Most isolates remained R5 (59 out of 61 isolates), although viruses using CXCR4 appeared in some cases of progression to AIDS. In several cases, a broad tropism was observed during the course of infection, with a frequent usage of BOB and Bonzo in addition to CCR5. Rapid progression to disease and short survival time among Central African HIV-1 patients appear more frequent than those reported in industrialized countries. Viral coreceptor used was mainly CCR5, but, interestingly, a large part of isolates also used BOB and Bonzo. However, there was no strict correlation between the clinical outcome and extended viral tropism.

Tuberculosis

Approximately one-third of the world population is infected with Mycobacterium tuberculosis, the organism that causes tuberculosis (TB). After a brief resurgence beginning in the mid-1980s, the incidence of TB is once again declining in the United States. Health care workers, including dentists and their staff, however, remain at risk for occupational acquisition of the disease. This risk can be managed by educating dental health care workers about the oral and systemic manifestations of TB and the mechanisms by which it is spread so that appropriate measures may be taken in the office to minimize the opportunity for disease transmission.

Pattern of bacterial diseases in a cohort of HIV-1 infected adults receiving cotrimoxazole prophylaxis in Abidjan, Côte d'Ivoire

BACKGROUND

WHO/UNAIDS recommended that cotrimoxazole should be prescribed in Africa in HIV-infected adults with CD4 cell counts < 500 x 10 /l, while closely monitoring bacterial diseases in as many settings as possible.

METHODS

Prospective cohort study, describing bacterial morbidity in adults receiving cotrimoxazole prophylaxis (960 mg daily) between April 1996 and June 2000 in Abidjan, Côte d'Ivoire.

RESULTS

Four-hundred and forty-eight adults (median baseline CD4 cell count 251 x 10 /l) were followed for a median time of 26 months. The rates of overall bacterial diseases and of serious bacterial diseases with hospital admission were 36.8/100 person-years (PY) and 11.3/100 PY, respectively. Bacterial diseases were the first causes of hospital admissions, followed by non-specific enteritis (10.2/100 PY), acute unexplained fever (8.4/100 PY), and tuberculosis (3.6/100 PY). Among serious bacterial diseases, the most frequent were enteritis (3.0/100 PY), invasive urogenital infections (2.5/100 PY), pneumonia (2.3/100 PY), bacteraemia with no focus (2.0/100 PY), upper respiratory tract infections (1.6/100 PY) and cutaneous infections (0.6/100 PY). Compared with patients with baseline CD4+ cell counts >or= 200 x 10 /l, other patients had an adjusted hazard ratio of serious bacterial diseases of 3.05 (95% confidence interval, 2.00-4.67; < 0.001). Seventy-five bacterial strains were isolated during serious episodes including 29 non-, 14, 12 spp, and 12.

DISCUSSION

Though with a medium-term rate half that of the short-term rate estimated under placebo before 1998 (26.1/100 PY), serious bacterial morbidity remains the first cause of hospital admission in adults receiving cotrimoxazole in this setting.

Opportunistic infections in patients with AIDS admitted to an university hospital of the Southeast of Brazil

Opportunistic diseases in HIV-infected patients have changed since the introduction of highly active anti-retroviral therapy (HAART). This study aims at evaluating the frequency of associated diseases in patients with AIDS admitted to an university hospital of Brazil, before and after HAART. The medical records of 342 HIV-infected patients were reviewed and divided into two groups: group 1 comprised 247 patients before HAART and, group 2, 95 patients after HAART. The male-to-female rate dropped from 5:1 to 2:1for HIV infection. There was an increase in the prevalence of tuberculosis and toxoplasmosis, with a decrease in Kaposi's sarcoma, histoplasmosis and cryptococcosis. A reduction of in-hospital mortality (42.0% vs. 16.9%; p = 0.00002) has also occurred. An agreement between the main clinical diagnoses and autopsy findings was observed in 10 out of 20 cases (50%). Two patients with disseminated schistosomiasis and 2 with paracoccidioidomycosis are reported. Overall, except for cerebral toxoplasmosis, it has been noticed a smaller proportion of opportunistic conditions related to severe immunosuppression in the post HAART group. There was also a significant reduction in the in-hospital mortality, possibly reflecting improvement in the treatment of the HIV infection.

Review of human immunodeficiency virus type 1-related opportunistic infections in sub-Saharan Africa

Understanding the natural history of human immunodeficiency virus type 1 (HIV-1) and opportunistic infections in sub-Saharan Africa is necessary to optimize strategies for the prophylaxis and treatment of opportunistic infections and to understand the likely impact of antiretroviral therapy. We undertook a systematic review of the literature on HIV-1 infection in sub-Saharan Africa to assess data from recent cohorts and selected cross-sectional studies to delineate rates of opportunistic infections, associated CD4 cell counts, and associated mortality. We searched the MEDLINE database and the Cochrane Database of Systematic Reviews and Cochrane Clinical Trials Register for English-language literature published from 1990 through April 2002. Tuberculosis, bacterial infections, and malaria were identified as the leading causes of HIV-related morbidity across sub-Saharan Africa. Of the few studies that reported CD4 cell counts, the range of cell counts at the time of diagnosis of opportunistic infections was wide. Policies regarding the type and timing of opportunistic infection prophylaxis may be region specific and urgently require further study.

Occurrence of Pneumocystis carinii in HIV-positive patients with suspected pulmonary tuberculosis in Ethiopia

OBJECTIVE

To investigate the prevalence of Pneumocystis carinii in consecutive HIV-positive patients with suspected pulmonary tuberculosis (PTB) attending a university hospital in Ethiopia.

METHODS

A PCR for P. carinii and an indirect immunoflorescence (IF) assay were performed on expectorated sputum samples from: 119 HIV-1-positive patients with negative smears and sputum cultures for Mycobacterium tuberculosis; 96 HIV-1-positive patients with culture-verified PTB; and 97 HIV-negative patients with negative mycobacterial cultures and 72 HIV-negative patients with culture-verified PTB, serving as controls. Outcome of PCR and IF were compared with the chest radiographic (CXR) and initial clinical diagnosis.

RESULTS

In the HIV+PTB- group, P. carinii was found in 10.9% by IF, 8.4% by single PCR (sPCR) and 30.3% by nested PCR (nPCR). In the HIV+PTB+ group, 3.1% were P. carinii positive by IF and sPCR and 13.5% by nPCR. All IF- and sPCR-positive samples were nPCR positive. In the HIV-PTB+ and HIV-PTB- groups, 4.2% and 3.1% were nPCR positive, respectively. Six out of eight HIV+PTB- patients with CXR suggesting P. carinii pneumonia (PCP) were IF and/or nPCR positive for P. carinii. In the IF-positive and nested PCR-positive HIV+PTB- patients more than one-third were interpreted as PTB by CXR whereas only one patient was diagnosed with clinical PCP.

CONCLUSIONS

P. carinii is prevalent in HIV-positive PTB suspects, suggesting that PCP may be an important, but not well recognized, differential diagnosis. Our findings have implications for treatment and primary prophylaxis for PCP in Ethiopia.

Splenic marginal zone atrophy and progressive CD8+ T-cell lymphocytosis in HIV infection: a study of adult post-mortem spleens from Côte d'Ivoire

AIMS

Progressive changes have been reported in lymph nodes in HIV infection, but few accounts describe altered splenic histology at different stages of the disease. Investigation of splenic changes accompanying the progressive CD4+ T-cell depletion that occurs in HIV infection could shed light on normal immunological interactions in this organ. Therefore, we assessed the amount and distribution of lymphoid tissue in spleens from adults with documented early or advanced HIV disease.

METHODS AND RESULTS

Immunohistochemistry was used to study splenic tissue collected in an extensive autopsy survey of HIV+ adults in West Africa. Compared with post-mortem spleens from HIV- West African adults and control UK spleens, those from HIV-infected patients showed severe atrophy of white pulp B- and T-cell compartments. In early and advanced HIV disease, marginal zone atrophy was significant. Peri-arteriolar lymphoid sheaths contained increased numbers of CD8+/CD45RO+ T-cells in advanced HIV disease. In red pulp, early and advanced cases showed a lymphocytosis of CD8+/CD45RO- T-lymphocytes.

CONCLUSIONS

Atrophic changes were more extreme in advanced than early HIV infection. Reduced marginal zone function possibly explains the known predisposition of HIV+ patients to infection by encapsulated bacteria. Possible immunological consequences of these CD8+/CD45RO+ (peri-arteriolar lymphoid sheaths) and CD8+/CD45RO- (red pulp) responses deserve further study. Comparison of West African and UK control spleens indicated that there were no major ethnic differences in spleen structure to prevent extrapolation of our results to European adults.

Risk factors for pneumonia in urban-dwelling HIV-infected women: a case-control study in Nairobi, Kenya

In sub-Saharan Africa, respiratory tract infections (RTI) are the leading cause of serious morbidity and mortality in HIV-infected persons. This study sought to investigate demographic, socioeconomic, and environmental risk factors for pneumonia in a cohort of HIV-infected women. The authors performed a nested case-control study in a cohort of HIV-1-infected adults followed in Nairobi, Kenya. Thirty-nine women who developed pneumonia during the follow-up period were selected as cases, and 66 women who did not develop pneumonia were randomly chosen to serve as control subjects. A questionnaire was administered in subjects' homes that assessed demographics, home environment, and socioeconomic status. Women were followed in the cohort for a median of 36.8 months (range, 27.3-39.3). Adjusting for length of follow-up period, factors associated with lower socioeconomic status (lower monthly spending [OR = 3.2; 95% CI, 1.2-8.4 per 10,000 Kenyan shilling decrease], having no savings [OR = 4.1; 95% CI, 1.4-11.9], less sturdy home construction material such as mud or cement walls [OR = 2.6; 95% CI, 1.1-5.9] or dirt floors [OR = 2.8; 95% CI, 1.0-7.6], and lack of a window in the home [OR = 5.5; 95% CI, 0.9-32.2]) and being widowed (OR = 4.3; 95% CI, 1.2-15.1) or single (OR = 3.3; 95% CI, 1.0-11.2) were associated with an increased risk of pneumonia. In multivariate analysis, widowed (AOR = 5.9; 95% CI, 1.3-26.3), single (AOR = 7.7; 95% CI, 1.6-36.4), and divorced (AOR = 4.5; 95% CI, 1.0-20.1) women, those without savings (AOR = 3.7; 95% CI, 1.2-11.7), and those living in more crowded and contagious conditions (AOR = 1.5; 95% CI, 1.1-2.1) remained at increased risk of pneumonia. If confirmed by prospective investigation, these findings could help identify persons and subpopulations of HIV-infected women with the greatest risk of pneumonia.

Pneumocystis carinii pneumonia in patients in the developing world who have acquired immunodeficiency syndrome

We review Pneumocystis carinii pneumonia (PCP) in patients in the developing world (i.e., Africa, Asia, the Philippines, and Central and South America) who have acquired immunodeficiency disease (AIDS). During the first decade of the AIDS pandemic, PCP rarely occurred in African adults. More recent reports have noted that PCP comprises a significantly greater percentage of cases of pneumonia than it did in the past. This trend dramatically contrasts with that observed in industrialized nations, where a reduction in the number of cases of PCP has occurred as a result of the widespread use of primary P. carinii prophylaxis and highly active antiretroviral therapy. Throughout the developing world, the rate of coinfection with Mycobacterium tuberculosis and PCP is high, ranging from 25% to 80%. Initiation of treatment when PCP is in an advanced stage may account for the high mortality rates (20%-80%) associated with pediatric PCP in the developing world.

Prevalence and indicators of HIV and AIDS among adults admitted to medical and surgical wards in Blantyre, Malawi

Despite high seroprevalence there are few recent studies of the effect of human immunodeficiency virus (HIV) on hospitals in sub-Saharan Africa. We examined 1226 consecutive patients admitted to medical and surgical wards in Blantyre, Malawi during two 2-week periods in October 1999 and January 2000: 70% of medical patients were HIV-positive and 45% had acquired immune deficiency syndrome (AIDS); 36% of surgical patients were HIV-positive and 8% had AIDS. Seroprevalence rose to a peak among 30-40 year olds; 91% of medical, 56% of surgical and 80% of all patients in this age group were HIV-positive. Seropositive women were younger than seropositive men (median age 29 vs. 35 years, P < 0.0001). Symptoms strongly indicative of HIV were history of shingles, chronic diarrhoea or fever or cough, history of tuberculosis (TB), weight loss and persistent itchy rash (adjusted odds ratios [AORs] all > 5). Clinical signs strongly indicative of HIV were oral hairy leukoplakia, shingles scar, Kaposi's sarcoma, oral thrush and hair loss (AORs all > 10). Of surgical patients with 'deep infections' (breast abscess, pyomyositis, osteomyelitis, septic arthritis and multiple abscesses), 52% were HIV-positive (OR compared with other surgical patients = 2.4). Severe bacterial infections, TB and AIDS caused 68% of deaths. HIV dominates adult medicine, is a major part of adult surgery, is the main cause of death in hospital and affects the economically active age group of the population.

Cloning, expression, purification, and crystallisation of HIV-2 reverse transcriptase

A purification procedure is described for the isolation of recombinant HIV-2 reverse transcriptase expressed in Escherichia coli. The p68 subunit is expressed, in the absence of induction, and use of a heparin-Sepharose column produces substantially pure protein. Concentration of the homodimeric p68 reverse transcriptase pool, followed by incubation at room temperature for several days, results in full conversion by E. coli proteases to the heterodimer (p68/p55). This extended incubation simplifies the purification process and improves the yield of heterodimeric reverse transcriptase, which shows a truncation of the smaller subunit to 427 residues. The protein is then purified further by hydroxyapatite and gel-filtration chromatography to homogeneity. The HIV-2 RT is active and has been used to produce crystals that diffract to beyond 3.0 A.

Autopsy-proven determinants of death in HIV-infected patients treated for pulmonary tuberculosis in Sao Paulo, Brazil

The aim of this work is to describe and compare pulmonary pathology and proven causes of death in HIV-infected and non-HIV patients treated for tuberculosis, to identify the presence and extension of the lesions, and to suggest appropriate interventions based on the results. Of 246 adult patients (aged > 15) autopsied with tuberculosis and tested for HIV infection at Hospital das Clinicas, School of Medicine, São Paulo University, from January 1994 to December 1996, 100 HIV-infected patients were matched with 44 non-HIV-infected patients. Demographic determinants influencing patients' death were as follows: 1. Age and sex were not found to be important for the histological outcome, but do seem to correlate with HIV infection. Older patients with tuberculosis are less likely to be HIV-infected; 2. Previous tuberculosis and its treatment had no influence on the course of secondary or reinfection tuberculosis; 3. The efficiency of the diagnostic criteria used at the time of death was very low (59.2%); 4. Tuberculosis was more frequently investigated in HIV-infected than in non-HIV-infected patients; 5. Only 79 (56%) of the patients received first line agents for treatment; 6. Patients presented with advanced disease; 7. Their mortality is high, and death occurs early. Morphological determinants with influence on patient's death were related to differences in the spectrum of tuberculosis presentation and time of treatment. Noncaseating generalized multibacillary tuberculosis was likely to be the primary cause of death in HIV-infected patients who died during therapy, whereas deaths of patients occurring after the second course of treatment because of recurrence or incomplete treatment were increased for other manifestations of HIV disease (pyogenic pneumonia, Pneumocystis carinii pneumonia, cerebral toxoplasmosis, wasting syndrome). In these patients, dimorphic tuberculosis, an intermediate reactive spectrum form of presentation, was the predominant histological finding. In the opposite spectrum, paucibacillary tuberculosis, a reactive form of tuberculosis presentation, was equally regarded in non-HIV-infected patients as the primary cause of death after four months of therapy. In the same spectrum, non-HIV-infected patients with tuberculosis, who completed all or most of their treatment, died of associated diseases after therapy (alcoholism, cancer, diabetes mellitus). Autopsy-proven determinants of death were associated with HIV status, the spectrum of tuberculosis presentation, and time of treatment. Early treatment for tuberculosis and associated diseases can improve survival and the quality of life even of highly immunosuppressed patients.

Management of HIV and AIDS in the African context

The initial response to the African HIV epidemic was to concentrate on the prevention of new infections. There is now an urgent need to address the health care requirements of large numbers of already infected individuals. The spectrum of disease in the African setting is dominated by tuberculosis, bacterial and protozoan infections. In much of Africa, health services are overwhelmed by the care of terminally ill AIDS patients. In the absence of specific HIV therapy, health care resources are being increasingly utilised, but with little survival benefit for the individual. Resources available for treating patients vary considerably between the richer and poorer countries of the continent. Primary prevention of opportunistic infections and maternal child transmission are at present affordable and cost-effective interventions. Whilst antiretroviral therapies may presently be unaffordable in much of Africa, they represent a modality that can have a major effect on HIV survival. The challenge is to improve the health and longevity of HIV-infected individuals with the rational use of the limited health resources available in Africa today.

Opportunistic infections associated with HIV infection in Africa

HIV-associated infections in sub-Saharan Africa differ markedly in their incidence from those in industrialized countries. Tuberculosis is the commonest cause of morbidity and mortality. Enteric pathogens such as microsporidiosis commonly cause disease as access to safe water is limited. Pneumocystis carinii pneumonia, which is the commonest opportunistic infection in industrialized countries, is uncommon in adults with HIV infection. This remains unexplained because P. carinii pneumonia is common in Black African HIV-infected children. Cytomegalovirus and Mycobacterium avium complex, which only occur in severely immune-suppressed individuals, are seldom found. One reason may be that survival after conversion to AIDS is relatively short in Africa. Patients often die before they develop severe immune suppression. Recently, prophylactic cotrimoxazole treatment was shown to be effective in symptomatic HIV-infected adults in Africa. Tuberculosis preventive therapy is also effective in Africa, at least in the medium term. It is hoped that these two affordable interventions will become available to large numbers of patients identified in voluntary counselling and testing centres.

Tuberculosis-related deaths within a well-functioning DOTS control program

To describe the molecular epidemiology of tuberculosis (TB)-related deaths in a well-managed program in a low-HIV area, we analyzed data from a cohort of 454 pulmonary TB patients recruited between March 1995 and October 2000 in southern Mexico. Patients who were sputum acid-fast bacillus smear positive underwent clinical and mycobacteriologic evaluation (isolation, identification, drug-susceptibility testing, and IS6110-based genotyping and spoligotyping) and received treatment from the local directly observed treatment strategy (DOTS) program. After an average of 2.3 years of follow-up, death was higher for clustered cases (28.6 vs. 7%, p=0.01). Cox analysis revealed that TB-related mortality hazard ratios included treatment default (8.9), multidrug resistance (5.7), recently transmitted TB (4.1), weight loss (3.9), and having less than 6 years of formal education (2). In this community, TB is associated with high mortality rates.

Structure of HIV-2 reverse transcriptase at 2.35-A resolution and the mechanism of resistance to non-nucleoside inhibitors

The HIV-2 serotype of HIV is a cause of disease in parts of the West African population, and there is evidence for its spread to Europe and Asia. HIV-2 reverse transcriptase (RT) demonstrates an intrinsic resistance to non-nucleoside RT inhibitors (NNRTIs), one of two classes of anti-AIDS drugs that target the viral RT. We report the crystal structure of HIV-2 RT to 2.35 A resolution, which reveals molecular details of the resistance to NNRTIs. HIV-2 RT has a similar overall fold to HIV-1 RT but has structural differences within the "NNRTI pocket" at both conserved and nonconserved residues. The structure points to the role of sequence differences that can give rise to unfavorable inhibitor contacts or destabilization of part of the binding pocket at positions 101, 106, 138, 181, 188, and 190. We also present evidence that the conformation of Ile-181 compared with the HIV-1 Tyr-181 could be a significant contributory factor to this inherent drug resistance of HIV-2 to NNRTIs. The availability of a refined structure of HIV-2 RT will provide a stimulus for the structure-based design of novel non-nucleoside inhibitors that could be used against HIV-2 infection.

The post-mortem pathology of HIV-1-infected African children

A retrospective review of autopsy findings and medical records in 33 HIV-infected children living in a Kenyan orphanage is described. Their ages ranged from 1 month to 18 years and median age at death was 71 months (range 7-156). Respiratory disorders were probably the primary cause of death in 21 (64%), in 19 (90%) of whom pyogenic parenchymal lung disease was detected. A presumptive clinical diagnosis of pulmonary tuberculosis had been made in 14 (67%); these children also had a history of recurrent acute lower respiratory tract infections (more than four infections/year). At autopsy, however, only one case of tuberculosis was identified (disseminated disease). Pneumocystis carinii pneumonia was not identified. Primary bacterial meningitis was detected in 33%. The associated findings included disseminated Kaposi sarcoma in two children and cryptococcal meningitis in one child. It is concluded that pyogenic infections are common causes of morbidity and mortality in HIV-1-infected African children. Management should include prompt treatment and, if indicated, prophylaxis for recurrent bacterial infections, and early evaluation and treatment of pulmonary tuberculosis.

Pulmonary manifestations of HIV/AIDS in the tropics

The most significant pulmonary opportunistic infections in the tropics are TB and pneumococcal pneumonia. Guidelines for the diagnosis and management of these and other pulmonary manifestations of HIV are discussed. Ultimately, unless concerted efforts are made to treat underlying HIV infection in regions most devastated by AIDS, the impact of these diseases will continue to grow.

Morbidity and mortality in South African gold miners: impact of untreated disease due to human immunodeficiency virus

A cohort of 1792 human immunodeficiency virus (HIV)-positive and 2970 HIV-negative South African miners was observed for 12 months starting in February 1998. All-cause hospitalizations and deaths were significantly associated with HIV infection (respective unadjusted incidence rate ratios, 2.9 and 9.2; respective 95% confidence intervals, 2.5-3.4 and 5.5-16.0). Tuberculosis (TB), bacterial pneumonia, cryptococcosis, and trauma were the major causes of admission for HIV-positive patients, whereas Pneumocystis carinii pneumonia was an uncommon cause (respective admission rates, 8.5, 6.9, 2.2, 6.0, and 0.53 admissions per 100 person-years). Enteritis, bronchitis, urinary tract infections, and soft-tissue infections were also significantly associated with HIV infection. Cryptococcosis caused 44% of deaths among HIV-positive patients. Trauma was the main hazard for HIV-negative men, causing 42% of admissions and 60% of deaths. A broad range of infectious conditions is significantly associated with HIV infection in South African miners. Identification and implementation of effective prophylactic regimens are urgently needed.

Tuberculosis unleashed: the impact of human immunodeficiency virus infection on the host granulomatous response to Mycobacterium tuberculosis

The granuloma plays a critical role in the host immune response to Mycobacterium tuberculosis, containing the organism and confining it in a latent state in most infected individuals. Indeed, approximately one-third of the world's population has latent M. tuberculosis infection. However, over the past decade, the human immunodeficiency virus type 1 (HIV-1) pandemic has profoundly affected the incidence and clinicopathological features of tuberculosis. This review examines the immunological mechanisms whereby HIV-1 impairs the establishment, maintenance and function of the tuberculous granuloma.

Causes and empirical treatment of fever in HIV-infected adult outpatients, Abidjan, Côte d'Ivoire

OBJECTIVES

In Abidjan, HIV prevalence has been estimated at 20% in outpatients attending community clinics. Documenting causes of fever in HIV-infected adult outpatients may help to improve care in these centres with limited facilities.

DESIGN

Prospective study.

METHODS

We describe all diagnoses and treatments made during febrile episodes in HIV-infected adults participating in the ANRS 059 trial and followed up in a dedicated outpatient centre.

RESULTS

Causes of fever could be identified in half of the 269 febrile episodes. Bacterial diseases were the leading identified cause of fever in all CD4 cell count strata (53, 56 and 43% of identified causes in episodes with CD4 count < 200 x 106/l, 200-499 x 106/l, and >or= 500 x 106/l, respectively), followed by malaria (5, 22, and 38%, respectively). Among febrile bacterial diseases, respiratory tract infections and enteritis accounted for 62% of organ involvement, and Streptococcus pneumoniae and non-typhi Salmonella represented 69% of isolated bacterial strains. In these bacterial episodes, an early empirical antibacterial treatment was associated with shorter duration of hospitalization and fever. In the 19 episodes leading to death (7%), the two leading diagnoses were atypical mycobacteriosis (26%) and acute unexplained fever (21%). Death was associated with the absence of antimalarial treatment in the group of acute unexplained fevers.

CONCLUSIONS

African HIV treatment guidelines should take into account the predominant role of bacterial infections and malaria in HIV-infected adult outpatients. Reports from other African settings would be useful to compare experiences in algorithms of empirical early antibacterial and antimalarial treatments.

Increased survival of persons with tuberculosis and human immunodeficiency virus infection, 1991--2000

To determine factors associated with the occurrence of human immunodeficiency virus (HIV) infection and tuberculosis (TB) disease (HIV-TB) and the associated survival rate, we analyzed patients with HIV-TB at Grady Memorial Hospital, Atlanta, Georgia, from 1991 through 2000. Overall, 644 patients with HIV-TB were seen. The number of HIV-TB cases per year was highest in 1992 (102 cases) and declined to 39 cases in 2000. Over time, patients were more likely to be enrolled in the HIV outpatient clinic (P<.01), but, in 1997, only 21 (51%) of 41 patients were enrolled in HIV-infection care programs and only 9 (22%) of 41 received HAART. The 1-year survival rate for patients with HIV-TB was 58% in 1991, 81% in 1994, and 83% in 1997 (P<.001). The increase in survival for patients with HIV-TB between 1991 and 1994 was likely due to improved TB and HIV therapy. More effective strategies for enrolling and maintaining HIV-TB patients in HIV-infection care programs could further increase survival.

A simple clinical and paraclinical score predictive of CD4 cells counts below 400/mm3 in HIV-infected adults in Dakar University Hospital, Senegal

In industrialized countries the decision to start co-trimoxazole (CMX) prophylaxis of HIV-related opportunistic infections is based on the CD4+ cell count. The value of CMX prophylaxis has also been demonstrated in Africa, where CD4+ cell counts are rarely available. We therefore developed a simple score predictive of a threshold CD4+ cell count (400/mm3) below which CMX prophylaxis is indicated. In a retrospective cross-sectional study, we collected clinical and biological data on 211 HIV-infected patients recruited from January 1996 through January 1998 at Fann University Hospital in Dakar, Senegal. Several variables were identified as being predictive of a CD4+ cell count below 400/mm3 by stepwise logistic regression. Each variable was weighted according to its regression coefficient, as follows: male sex (+1), weight loss (+2), body mass index < 22 (+2), herpes zoster (+4), tuberculin induration < 5 mm (+3) and haemoglobin < or = 10 g/dL (+1). A score of > or = 4 (sum of weights) selected patients with CD4+ cell counts below 400/mm3 with a sensitivity of 98% and a negative predictive value of 83%. Such a score should be applicable in the African context and should facilitate the management of HIV-infected patients, especially the prescription of CMX prophylaxis.

HIV-1-related morbidity in adults, Abidjan, Côte d'Ivoire: a nidus for bacterial diseases

We studied mortality and morbidity in 270 HIV-1-infected adults (60% women, median age 31 years, mean baseline CD4 count 331/mm(3) ) observed in a follow-up that lasted a median 10 months in Côte d'Ivoire. Survival and probability of remaining free from any episode of morbidity at 12 months were 0.80 and 0.50, respectively. Baseline CD4 count <200/mm(3) was the only variable associated with global morbidity and mortality, with hazard ratios of 2.50 and 7.57, respectively. The most frequent causes of morbidity were severe bacterial infections (incidence rate: 26.1 per 100 person-years [py]), followed by oral candidiasis (22.3% py), unexplained weight loss over 10% of baseline body weight (13.3% py), tuberculosis (10.1% py), unexplained chronic diarrhea (9.7% py), and isosporiasis (5.1% py). Nontyphoid Salmonella accounted for 37% of isolated strains during severe bacterial infections, followed by Streptococcus pneumoniae (34%), Escherichia coli (15%), and Shigella species (7%). A significant part of bacterial morbidity occurred in patients with baseline CD4 count > or = 200/mm(3), in whom the incidence rate of bacterial diseases was 21.3% py and the probability of remaining free from any bacterial infection at 12 months was 0.80 (vs. 36.4% py and 0.71 in patients with baseline CD4 count <200/mm(3); p =.07).

Prevalence and clinical manifestations of disseminated Mycobacterium avium complex infection in South Africans with acquired immunodeficiency syndrome

In a sample of 100 hospitalized human immunodeficiency virus-seropositive black South African patients with CD4 cell counts of <100 cells/mm(3), the point prevalence of disseminated Mycobacterium avium complex infection was 10%, in contrast with other African studies that report that the infection is uncommon. The point prevalence of Mycobacterium tuberculosis was 54%. The clinical and laboratory features of these patients were largely unhelpful in detecting M. avium complex; the BACTEC blood culture (Becton Dickinson) was the only reliable method.

Pulmonary pathology in patients with AIDS: an autopsy study from Mumbai

OBJECTIVE

Although India has a high prevalence of HIV/AIDS, the associated pathologies responsible for morbidity have not been evaluated previously in a representative study. Hence, an autopsy study was carried out to analyse the spectrum of pulmonary lesions in patients with HIV/AIDS.

METHODS

A retrospective and prospective autopsy study was carried out during 1988-2000 at Mumbai, India. Lungs from 143 adults, with at least 10 sections from each case, were examined using routine and special stains.

RESULTS

The risk factors for 97 men (68%) and 38 women (27%) included: heterosexual sex with multiple partners (135 cases, 95%); blood transfusions (three cases; 2%); sex between men (two cases; 1%); and unknown risk factors (three cases, 2%). Pulmonary pathology was observed in 126 (88%) cases. The lesions identified were tuberculosis (85 cases, 59%), bacterial pneumonia (26 cases, 18%), cytomegalovirus (CMV) infection (10 cases, 7%), cryptococcosis (eight cases, 6%), Pneumocystis carinii pneumonia (seven cases, 5%), aspergillosis (four cases, 3%), toxoplasmosis (two cases, 1%), Kaposi's sarcoma (one case, 1%), squamous cell carcinoma (one case, 1%). Two or more infections were observed in 18 (13%) cases.

CONCLUSIONS

Pulmonary diseases and risk factors among patients with AIDS in India differ from those reported in industrialized countries. Tuberculosis was the most frequently observed pulmonary infection, followed by bacterial pneumonia and CMV pneumonitis. In contrast with industrialized countries, PCP remains less common in our patients. The information on opportunistic infections obtained in this study will be useful for managing HIV/AIDS cases at district level hospitals where diagnosing specific HIV-associated diseases is not always possible.

Association between Kaposi's sarcoma and atherosclerosis: implications for gammaherpesviruses and vascular disease

The treatment of HIV-positive patients with protease inhibitors has been suggested to increase their risk of atherosclerosis. The cause of this accelerated atherogenesis is unknown, but on the basis of previous studies we postulated that it could be linked to the presence of human herpesvirus-8. A retrospective analysis of post-mortem reports showed a strong correlation between Kaposi's sarcoma and the presence of atheroma. This hypothesis merits further investigation.

Prophylaxis with trimethoprim-sulfamethoxazole for human immunodeficiency virus-infected patients: impact on risk for infectious diseases

Trimethoprim-sulfamethoxazole (TMP-SMZ) is widely prescribed as prophylaxis for Pneumocystis carinii pneumonia (PCP) in human immunodeficiency virus (HIV)-infected persons. Its efficacy against other infections has not been thoroughly evaluated. To compare the risk for infectious diseases for persons who were prescribed TMP-SMZ with that for patients who were not prescribed TMP-SMZ, we examined data collected from the medical records of HIV-infected patients (January 1990 through September 1999) who were enrolled in the Adult and Adolescent Spectrum of HIV Disease Project. During intervals when patients had CD4(+) T lymphocyte counts of <200 cells/microL (19,081 persons; 22,801 person-years), prescription of TMP-SMZ was associated with significant protection from toxoplasmosis, salmonellosis, infection with Haemophilus species, invasive or any staphylococcal infection, and PCP, but not from Shigella, pneumococcal or nonpneumococcal Streptococcus, Klebsiella, or Pseudomonas species. We demonstrate that prescription of TMP-SMZ for PCP prophylaxis in persons with HIV infection is associated with significantly decreased risk for several infectious diseases. These findings may be of interest to HIV prevention programs in resource-poor countries.

Cerebrospinal fluid

A quick and accurate diagnosis of maladies affecting the central nervous system (CNS) is imperative. Procurement and analysis of cerebrospinal fluid (CSF) are paramount in helping the clinician determine a patient's clinical condition. Various staining methods, measurement of white blood cell counts, glucose and protein levels, recognition of xanthochromia, and microbiologic studies are CSF parameters that are collectively important in the ultimate determination by a clinician of the presence or absence of a catastrophic CNS condition. Many of these CNS parameters have significant limitations that should be recognized to minimize under treating patients with catastrophic illness.

Respiratory tract infection in HIV-1-infected adults in Nairobi, Kenya: evaluation of risk factors and the world health organization treatment algorithm

To evaluate the WHO (World Health Organization) algorithm for management of respiratory tract infection (RTI) in HIV-1-infected adults and determine risk factors associated with RTI, we enrolled a cohort of 380 HIV-1-seropositive adults prospectively followed for incident RTI at an outpatient clinic in Nairobi, Kenya. RTI was diagnosed when patients presented with history of worsening or persistent cough. Patients were treated with ampicillin, or antituberculosis therapy when clinically indicated, as first-line therapy and with trimethoprim/sulfamethoxazole as second-line therapy. Five hundred ninety-seven episodes of RTI were diagnosed: 177 of pneumonia and 420 of bronchitis. The WHO RTI algorithm was used for 401 (95%) episodes of bronchitis and 151 (85%) episodes of pneumonia (p <.001). Three percent of bronchitis cases versus 32% of pneumonia cases failed to respond to first-or second-line treatment (p <.0001). Being widowed (adjusted odds ratio [OR] = 2.1, 95% confidence interval [CI]: 1.0-4.4), less than 8 years of education (adjusted OR = 2.5, CI: 1.5 - 4.1), and CD4 count < 200 cells/microl (adjusted OR = 2.4, CI: 1.4-3.9) were risk factors for pneumonia. A high percentage of patients (32%) with pneumonia required a change in treatment from that recommended by the WHO guidelines. Randomized trials should be performed to determine more appropriate treatment strategies in HIV-1-infected individuals.

Trends in bloodstream infections among human immunodeficiency virus-infected adults admitted to a hospital in Nairobi, Kenya, during the last decade

Bloodstream infections are a frequent complication in human immunodeficiency virus (HIV)-infected adults in Africa and usually associated with a poor prognosis. We evaluated bloodstream infections across a decade in 3 prospective cross-sectional surveys of consecutive medical admissions to the Kenyatta National Hospital, Nairobi, Kenya. Participants received standard clinical care throughout. In 1988-1989, 29.5% (28 of 95) of HIV-positive patients had bloodstream infections, compared with 31.9% (46 of 144) in 1992 and 21.3% (43 of 197) in 1997. Bacteremia and mycobacteremia were significantly associated with HIV infection. Infections with Mycobacterium tuberculosis, non-typhi species of Salmonella (NTS), and Streptococcus pneumoniae predominated. Fungemia exclusively due to Cryptococcus neoformans was uncommon. Clinical features at presentation remained similar. Significant improvements in the survival rate were recorded among patients with NTS bacteremia (20%-83%; P<.01) and mycobacteremia (0%-73%; P<.01). Standard clinical management can improve outcomes in resource-poor settings.

Pneumocystis carinii pneumonia in patients being registered for smear-negative pulmonary tuberculosis in Malawi

The National TB Control Programme of Malawi registers and treats large numbers of patients with chronic cough for smear-negative pulmonary tuberculosis (PTB). Smear-negative PTB is diagnosed according to clinical and radiographic criteria, as mycobacterial cultures are not routinely available. In an area of high HIV seroprevalence there is a concern that other opportunistic infections apart from TB, such as Pneumocystis carinii, may be missed owing to lack of diagnostic facilities. The aims of this study were to investigate (i) the extent of P. carinii pneumonia (PCP) in patients about to be registered for smear-negative PTB; (ii) whether there were any clinical or radiological features that could help identify PCP in the absence of more detailed investigations; and (iii) the treatment outcome of PCP patients. A cohort of 352 patients who were about to be started on treatment for smear-negative PTB were investigated further in 1997-99 by clinical assessment, HIV testing and bronchoscopy. HIV sero-prevalence was 89% (278/313). A total of 186 patients underwent bronchoscopy and bronchoalveolar lavage, and PCP was diagnosed by indirect immunofluorescence or polymerase chain reaction in 17 (9%) of this subgroup. Dyspnoea was significantly more common in PCP cases compared to non-PCP cases (RR 1.35; 95% CI 1.24-1.48; P = 0.008), but discrimination between the groups was difficult using clinical criteria alone. The outcome of PCP cases was poor despite management with high-dose co-trimoxazole and secondary co-trimoxazole prophylaxis, with a median survival of 4 months (25-75% range: 2-12 months).

Necropsies in African children: consent dilemmas for parents and guardians

BACKGROUND

Necropsy examination provides a good index of the accuracy of clinical diagnosis and the quality of treatment, but its use in sub-Saharan Africa is limited.

AIMS

To identify the main reasons for parents'/guardians' refusal of consent for necropsy and to explore the issues affecting their decision.

METHODS

A sequential necropsy study of Zambian children between 2 months and 15 years dying of respiratory disease. When the parent/guardian refused permission for necropsy, the main reason given was recorded, after encouragement to express their specific concerns in their own words.

RESULTS

Parents/guardians of 891 of 1181 children (75.4%) refused to give permission, and 290 (24.6%) consented. Of those who refused, 43% did so on the grounds that it would be a "waste of time," as the diagnosis should have been made in life and the findings would now be of no benefit to them. More than one quarter of those who refused did so because a death certificate had already been issued and arrangements to transport the body had been made and could not be delayed. Traditional beliefs that ancestral spirits forbade the mutilation of dead bodies were cited by 77 (8.6%). Other reasons included the child not being their own or that they must seek permission from other family members who were not available (6%). Religious beliefs were not a major cause of refusal.

CONCLUSIONS

It is possible to achieve a rate of necropsy consent sufficient to undertake valuable clinical pathology studies on children in sub-Saharan Africa. The wide range of reasons cited for refusal points to the diverse and complex interaction of social and cultural factors affecting attitudes to necropsy examination. Medical staff need training and support to improve the uptake of clinical pathology services.

Update on the pathology of AIDS

The acquired immune deficiency syndrome (AIDS) is the result of a human immunodeficiency virus (HIV) infection damaging the cell-mediated immune system. HIV infection is a zoonosis that has affected man for at least 50 years, though the disease has become pandemic only in the last 2 decades. A wide range of opportunistic infections (Ols) and tumours develop; additionally, HIV directly damages some organs. The patterns of opportunistic diseases (ODs) are significantly different in different parts of the world, depending on the local prevalences of latent and acquired infections and on the survival of HIV-infected patients. OD patterns change as peoples migrate. Recent highly active anti-retroviral (HIV) chemotherapy prevents many of the common Ols, but also induces a new range of toxic pathological damage, e.g. the liver, and lipid metabolism. Longer survival permits development of new HIV-related diseases, e.g. the lymphoproliferative disorders. The pathology of HIV/AIDS is not static but changing.