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

Pediatric Cryptococcosis

BACKGROUND

Seroprevalence studies have shown that 70% of children are exposed to Cryptococcus , the most common cause of meningitis in people living with human immunodeficiency virus (HIV), but reported pediatric disease prevalence is much lower than in adults.

METHODS

PubMed and Ovid Global Health databases were searched with the terms "cryptococcosis," "cryptococcal meningitis," " Cryptococcus neoformans " or " Cryptococcus gattii ." All studies reporting pediatric specific data in the English language from 1980 up until December 2022 were included.

RESULTS

One hundred sixty-eight publications were reviewed totaling 1469 children, with the majority reported from Africa (54.2%). Sixty-five percent (961) were HIV positive, 10% (147) were non-HIV immunocompromised and 19% (281) were immunocompetent. Clinical signs and symptoms were only reported for 458 children, with fever (64%), headache (55%) and vomiting (39%) being the most common. Most children (80%) suffered from meningoencephalitis. Lung involvement was rarely described in HIV-positive children (1%), but significantly more common in the non-HIV immunocompromised (36%) and immunocompetent (40%) groups ( P < 0.0001). Only 22% received the recommended antifungal combination therapy, which was significantly higher in immunocompetent children than those with HIV (39% vs. 6.8%; P < 0.0001). Overall mortality was 23%. A significant higher mortality was observed in children with HIV compared with immunocompetent children (32% vs. 16%; P < 0.001), but not compared with children with non-HIV immunosuppression (25).

CONCLUSIONS

This is the largest review of pediatric cryptococcosis with new observations on differences in clinical presentation and outcome depending on the underlying condition. The lack of granular clinical data urges prospective clinical epidemiological studies for improved insight in the epidemiology, management and outcome of cryptococcosis in children.

Effect of HIV status and antiretroviral treatment on treatment outcomes of tuberculosis patients in a rural primary healthcare clinic in South Africa

BACKGROUND

Tuberculosis (TB) remains the leading cause of death among human immunodeficiency virus (HIV) infected individuals in South Africa. Despite the implementation of HIV/TB integration services at primary healthcare facility level, the effect of HIV on TB treatment outcomes has not been well investigated. To provide evidence base for TB treatment outcome improvement to meet End TB Strategy goal, we assessed the effect of HIV status on treatment outcomes of TB patients at a rural clinic in the Ugu Health District, South Africa.

METHODS

We reviewed medical records involving a cohort of 508 TB patients registered for treatment between 1 January 2013 and 31 December 2015 at rural public sector clinic in KwaZulu-Natal province, South Africa. Data were extracted from National TB Programme clinic cards and the TB case registers routinely maintained at study sites. The effect of HIV status on TB treatment outcomes was determined by using multinomial logistic regression. Estimates used were relative risk ratio (RRR) at 95% confidence intervals (95%CI).

RESULTS

A total of 506 patients were included in the analysis. Majority of the patients (88%) were new TB cases, 70% had pulmonary TB and 59% were co-infected with HIV. Most of HIV positive patients were on antiretroviral therapy (ART) (90% (n = 268)). About 82% had successful treatment outcome (cured 39.1% (n = 198) and completed treatment (42.9% (n = 217)), 7% (n = 39) died 0.6% (n = 3) failed treatment, 3.9% (n = 20) defaulted treatment and the rest (6.6% (n = 33)) were transferred out of the facility. Furthermore, HIV positive patients had a higher mortality rate (9.67%) than HIV negative patients (2.91%)". Using completed treatment as reference, HIV positive patients not on ART relative to negative patients were more likely to have unsuccessful outcomes [RRR, 5.41; 95%CI, 2.11-13.86].

CONCLUSIONS

When compared between HIV status, HIV positive TB patients were more likely to have unsuccessful treatment outcome in rural primary care. Antiretroviral treatment seems to have had no effect on the likelihood of TB treatment success in rural primary care. The TB mortality rate in HIV positive patients, on the other hand, was higher than in HIV negative patients emphasizing the need for enhanced integrated management of HIV/TB in rural South Africa through active screening of TB among HIV positive individuals and early access to ART among HIV positive TB cases.

AIDS-defining causes of death from autopsy findings for HIV-positive individuals in sub-Saharan Africa in the pre- and post-ART era: A systematic review and meta-analyses

Background: The lack of representative data on causes of death in sub-Saharan Africa (SSA) hampers our understanding of the regional burden of HIV and impact of interventions. In spite of the roll-out of antiretroviral therapy (ART) programs, HIV-infected individuals are still dying from complications of AIDS in SSA. We reviewed autopsy findings in SSA to observe whether the prevalence of 14 AIDS-defining illnesses changed from the pre-ART era to the post-ART era. Methods: We conducted a systematic review of autopsy findings in SSA using Medline, CINAHL, Evidence Based Medicine, EMBASE, Scopus, Web of Science, and abstracts from the Conference on Retroviruses and Opportunistic Infections, for literature published between January 1, 1990 and September 30, 2018. We focused on 14 AIDS-defining illnesses as causes of death. Results: In total, 33 studies were identified, including 9 from South Africa, 4 from the Ivory Coast, and the rest from eastern regions of sub-Saharan Africa. Of these, 18 studies were included in the meta-analyses for each of the AIDS-defining illnesses for adults. A ‘mixed group’ of studies that included adults and children was used for separate meta-analyses. Most opportunistic infections (OIs) showed a decrease in prevalence, with the notable exception of tuberculosis (TB), which showed a 13% increase in adult deaths and a 5% increase in mixed population group deaths. Kaposi’s sarcoma and non-Hodgkin’s lymphoma both showed a notable increase in prevalence, and liver disease showed a 10% increase in prevalence in the adult group. Conclusions: Even though ART has reduced the contribution of OIs to causes of death for people infected with HIV in SSA, targeted and strategic efforts are needed in order to strengthen existing prevention, diagnosis, and treatment of TB. More research is required to understand the complex role ARTs have on liver and kidney diseases.

Prevalence of tuberculosis in post-mortem studies of HIV-infected adults and children in resource-limited settings: a systematic review and meta-analysis

Objectives:

Tuberculosis (TB) is estimated to be the leading cause of HIV-related deaths globally. However, since HIV-associated TB frequently remains unascertained, we systematically reviewed autopsy studies to determine the true burden of TB at death.

Methods:

We systematically searched Medline and Embase databases (to end 2013) for literature reporting on health facility-based autopsy studies of HIV-infected adults and/or children in resource-limited settings. Using forest plots and random-effects meta-analysis, we summarized the TB prevalence found at autopsy and used meta-regression to explore variables associated with autopsy TB prevalence.

Results:

We included 36 eligible studies, reporting on 3237 autopsies. Autopsy TB prevalence was extremely heterogeneous (range 0–64.4%), but was markedly higher in adults [pooled prevalence 39.7%, 95% confidence interval (CI) 32.4–47.0%] compared to children (pooled prevalence 4.5%, 95% CI 1.7–7.4%). Post-mortem TB prevalence varied by world region, with pooled estimates in adults of 63.2% (95% CI 57.7–68.7%) in South Asia (n = 2 studies); 43.2% (95% CI 38.0–48.3) in sub-Saharan Africa (n = 9 studies); and 27.1% (95% CI 16.0–38.1%) in the Americas (n = 5 studies). Autopsy prevalence positively correlated with contemporary estimates of national TB prevalence. TB in adults was disseminated in 87.9% (82.2–93.7%) of cases and was considered the cause of death in 91.4% (95% CI 85.8–97.0%) of TB cases. Overall, TB was the cause of death in 37.2% (95% CI 25.7–48.7%) of adult HIV/AIDS-related deaths. TB remained undiagnosed at death in 45.8% (95% CI 32.6–59.1%) of TB cases.

Conclusions:

In resource-limited settings, TB accounts for approximately 40% of facility-based HIV/AIDS-related adult deaths. Almost half of this disease remains undiagnosed at the time of death. These findings highlight the critical need to improve the prevention, diagnosis and treatment of HIV-associated TB globally.

Dysregulation of claudin-5 in HIV-induced interstitial pneumonitis and lung vascular injury. Protective role of peroxisome proliferator-activated receptor-γ

RATIONALE

HIV-1-induced interstitial pneumonitis (IP) is a serious complication of HIV-1 infection, characterized by inflammation and cellular infiltration in lungs, often leading to respiratory failure and death. The barrier function of the pulmonary endothelium is caused in part by tight junction (TJ) proteins, such as claudin-5. Peroxisome proliferator-activated receptor (PPAR)-γ is expressed in lung tissues and regulates inflammation. We hypothesize that HIV-1 induces vascular lung injury, and HIV-1-mediated damage of the pulmonary endothelium and IP is associated with dysregulation of PPAR-γ.

OBJECTIVES

Investigate the effects of HIV-1 infection on the pulmonary microvasculature and the modulatory effects of the PPAR-γ ligands.

METHODS

Using human lung tissues, we demonstrated down-regulation of claudin-5 (marker of pulmonary barrier integrity), down-regulation of PPAR-γ transcription, and expression in lung tissues of HIV-1-infected humans with IP.

MEASUREMENTS AND MAIN RESULTS

Human lung microvascular endothelial cells expressed the TJ proteins claudin-5, ZO-1, and ZO-2; HIV-1 decreased TJ proteins expression and induced nuclear factor-κB promoter activity, which was reversed by PPAR-γ agonist. Using two murine HIV/AIDS models, we demonstrated decreased claudin-5 expression and increased macrophage infiltration in the lungs of HIV-1-infected animals. Activation of PPAR-γ prevented HIV-1-induced claudin-5 down-regulation and significantly reduced viremia and pulmonary macrophage infiltration.

CONCLUSIONS

HIV-induced IP is associated with injury to the lung vascular endothelium, with decreased TJ and PPAR-γ expression, and increased pulmonary macrophage infiltration. PPAR-γ ligands abrogated these effects. Thus, regulation of PPAR-γ can be a therapeutic approach against HIV-1-induced vascular damage and IP in infected humans. Removal of Expression of Concern: Issues leading to the previous expression of concern for this article have been resolved after further revisions and editorial review. No further concerns exist.

Deaths due to respiratory tract infections in Africa: a review of autopsy studies

PURPOSE OF REVIEW

According to the WHO, lower respiratory tract infections are one of the most prevalent causes of death in Africa. Estimates based on verbal autopsies are inaccurate compared with the gold standard for determining cause of death, the anatomical postmortem. Here, we review all respiratory postmortem data available from Africa and assess disease prevalence by HIV status in both adults and children.

RECENT FINDINGS

Pulmonary and extrapulmonary tuberculosis was detected in over 50% of HIV-infected adults, four to five-fold more prevalent than in HIV-uninfected cases. Overall tuberculosis was less prevalent in children, but was more prevalent in HIV-uninfected compared with HIV-infected children. Bacterial pneumonia was more prevalent in children than adults and was relatively unaffected by HIV status. Pneumocystis jirovecci and human cytomegalovirus pneumonia were detected almost exclusively in HIV-infected mortalities, twice as prevalent in children as in adults. Coinfections were common and correlation with premortem clinical diagnoses was low.

SUMMARY

Respiratory tract infections are important causes of mortality in Africa. Of the 21 reviewed studies, only four studies (all adults) were undertaken in the last decade. There is hence an urgent need for new postmortem studies to monitor cause of death in new and emerging patient groups, such as those on antiretroviral therapy and HIV exposed uninfected children.

Causes of death on antiretroviral therapy: a post-mortem study from South Africa

Background

Mortality in the first months of antiretroviral therapy (ART) is a significant clinical problem in sub-Saharan Africa. To date, no post-mortem study has investigated the causes of mortality in these patients.

Methods

HIV-positive adults who died as in-patients at a Johannesburg academic hospital underwent chart-review and ultrasound-guided needle autopsy for histological and microbiological examination of lung, liver, spleen, kidney, bone marrow, lymph node, skin and cerebrospinal fluid. A clinico-pathologic committee considered all available data and adjudicated immediate and contributing causes of death.

Results

Thirty-nine adults were enrolled: 14 pre-ART, 15 early-ART (7–90 days), and 10 late-ART (>90 days). Needle sampling yielded adequate specimen in 100% of kidney, skin, heart and cerebrospinal fluid samples, 97% of livers and lungs, 92% of bone marrows, 87% of spleens and 68% of lymph nodes. Mycobacterial infections were implicated in 69% of deaths (26 of 27 of these due to M. tuberculosis), bacterial infections in 33%, fungal infections in 21%, neoplasm in 26%, and non-infectious organ failure in 26%. Immune reconstitution inflammatory syndrome (IRIS) was implicated in 73% of early-ART deaths. Post-mortem investigations revealed previously undiagnosed causes of death in 49% of cases. Multiple pathologies were common with 62% of subjects with mycobacterial infection also having at least one other infectious or neoplastic cause of death.

Conclusions

Needle biopsy was efficient and yielded excellent pathology. The large majority of deaths in all three groups were caused by M. tuberculosis suggesting an urgent need for improved diagnosis and expedited treatment prior to and throughout the course of antiretroviral therapy. Complex, unrecognized co-morbidities pose an additional challenge.

An autopsy study describing causes of death and comparing clinico-pathological findings among hospitalized patients in Kampala, Uganda

Background

Information on causes of death in HIV-infected patients in Sub-Saharan Africa is mainly derived from observational cohort and verbal autopsy studies. Autopsy is the gold standard to ascertain cause of death. We conducted an autopsy study to describe and compare the clinical and autopsy causes of death and contributory findings in hospitalized HIV-infected and HIV-uninfected patients in Uganda.

Methods

Between May and September 2009 a complete autopsy was performed on patients that died on a combined infectious diseases gastroenterology ward in Mulago Hospital in Kampala, Uganda. Autopsy cause of death and contributing findings were based on the macro- and microscopic post-mortem findings combined with clinical information. Clinical diagnoses were reported by the ward doctor and classified as confirmed, highly suspected, considered or not considered, based on information derived from the medical chart. Results are reported according to HIV serostatus.

Results

Fifty-three complete autopsies were performed in 66% HIV-positive, 21% HIV-negative and 13% patients with an unknown HIV serological status. Infectious diseases caused death in 83% of HIV-positive patients, with disseminated TB as the main diagnosis causing 37% of deaths. The spectrum of illness and causes of death were substantially different between HIV-positive and HIV-negative patients. In HIV-positive patients 12% of postmortem diagnoses were clinically confirmed, 27% highly suspected, 16% considered and 45% not considered. In HIV-negative patients 17% of postmortem diagnoses were clinically highly suspected, 42% considered and 42% not considered.

Conclusion

Autopsy examination remains an important tool to ascertain causes of death particularly in settings with limited access to diagnostic testing during life. HIV-positive patients continue to die from treatable and clinically undiagnosed infectious diseases. Until rapid-point of care testing is available to confirm common infections, empiric treatment should be further investigated.

Post-mortem histological pulmonary analysis in patients with HIV/AIDS

OBJECTIVES

Certain aspects of pulmonary pathology observed in autopsies of HIV/AIDS patients are still unknown. This study considers 250 autopsies of HIV/AIDS patients who died of acute respiratory failure and describes the demographic data, etiology, and histological pulmonary findings of the various pathologies.

METHODS

The following data were obtained: age, sex, and major associated diseases (found at the autopsy). Pulmonary histopathology was categorized as: diffuse alveolar damage; pulmonary edema; alveolar hemorrhage; and acute interstitial pneumonia. Odds ratio of the HIV/AIDS-associated diseases developing a specific histopathological pattern was determined by logistic regression.

RESULTS

A total of 197 men and 53 women were studied. The mean age was 36 years. Bacterial bronchopneumonia was present in 36% (91 cases) and Pneumocystis jiroveci pneumonia in 27% (68) of patients. Pulmonary histopathology showed acute interstitial pneumonia in 40% (99), diffuse alveolar damage in 36% (89), pulmonary edema in 13% (33), and alveolar hemorrhage in 12% (29) of patients. Multivariate analysis showed a significant and positive association between Pneumocystis jiroveci pneumonia and acute interstitial pneumonia (Odds ratio, 4.51; 95% CI, 2.46-8.24; p<0.001), severe sepsis and/or septic shock and diffuse alveolar damage (Odds ratio, 3.60; 95% CI, 1.78-7.27; p<0.001), and cytomegalovirus and acute interstitial pneumonia (Odds ratio, 2.22; 95% CI, 1.01-4.93; p=0.05).

CONCLUSIONS

This report is the first autopsy study to include demographic data, etiologic diagnosis, and respective histopathological findings in patients with HIV/AIDS and acute respiratory failure. Further studies are necessary to elucidate the complete pulmonary physiopathological mechanism involved with each HIV/AIDS-associated disease.

T-cell depletion and immunity to malaria in HIV-infections

Although early reports on HIV and malaria in co-infected subjects indicated little apparent interaction between the two infections, more recent investigations have found evidence for HIV increasing the risk from malaria. Conversely, increased viral load in susceptible cells occurs in malaria-infected people. However, the overall pattern of results is still somewhat confusing and contradictory. While morbidity from malaria may be greater in HIV-positive patients and in several reports the mortality risk is also higher, major increases in blood-stage parasitaemias that one might expect are not generally observed. The results of surveys are summarized and discussed in the context of what is known of malaria and HIV immunology in the light of recent data from humans as well as animal models.

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.

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.

The management of bacterial meningitis in children

Bacterial meningitis is still a major cause of death and disability in children worldwide. With the advent of conjugate vaccines against the three major pathogens, the burden of disease is increasingly concentrated in developing countries that cannot afford the vaccines. Antibiotic resistance is an increasing problem; in developed countries, high-level resistance to beta-lactams among Streptococcus pneumoniae necessitates the addition of vancomycin to third-generation cephalosporins. In many developing countries, the problems are more fundamental. Increasing resistance of S. pneumoniae to penicillin and chloramphenicol and of Haemophilus influenzae to chloramphenicol means that many children with bacterial meningitis receive ineffective treatments, as third-generation cephalosporins are often unavailable or unaffordable. Case fatality rates are as high as 50% and neurological sequelae occur in one-third of survivors. The use of corticosteroids in meningitis is controversial; the evidence that they protect against neurological complications of childhood meningitis (particularly severe hearing loss) is strongest when: meningitis is caused by H. influenzae type b; dexamethasone is given before the first dose of antibiotics; a bactericidal antibiotic such as a third-generation cephalosporin is used; and in the early stages of the infection. There are few controlled clinical trials on which to base recommendations about other adjuvant therapy for meningitis. Avoidance of secondary brain injury from hypoxia, hypotension, hypo-osmolarity and cerebral oedema, hypoglycaemia or convulsions is essential for a good outcome. The problem of bacterial meningitis will only be solved if protein-conjugate vaccines (or other effective vaccine strategies) against S. pneumonia, H. influenzae and epidemic strains of Neisseria meningitidis are available to all the world's children. Making third-generation cephalosporins affordable in the developing world is also a necessary intervention, but better antibiotics will not overcome the problems of poor access to hospitals and late presentation with established brain injury, and will inevitably bring further pressure for antimicrobial resistance.

HIV and respiratory infections in children

Respiratory disease is a frequent cause of morbidity and mortality in children infected with human immunodeficiency virus (HIV). This review highlights recent data and developments that relate to the impact of HIV on respiratory infections particularly in African children. Autopsy and clinical studies continue to show that bacterial pneumonia and Pneumocystis jiroveci pneumonia (PCP) are common respiratory infections and causes of death in regions where antiretroviral therapy and PCP prophylaxis are not routinely practiced. Recent studies of Zambian and South African children showed that pulmonary tuberculosis is more common in HIV-infected children than was previously recognized. The trial of bacterial conjugate vaccines in Johannesburg will provide important information of efficacy in an HIV endemic population. Prospective clinical descriptive and intervention studies are needed from different regions to guide clinical management and prevention of respiratory infections in HIV-infected children living in resource-poor countries.

Viral coinfections among African children infected with human immunodeficiency virus type 1

City-dwelling children from Kenya who were infected with human immunodeficiency virus type 1 (HIV-1) were tested for coinfection with cytomegalovirus (CMV), human T cell lymphotropic viruses 1 and 2, Kaposi sarcoma-associated herpesvirus (KSHV), or hepatitis B, C, and G viruses. All children were found to be coinfected with CMV, whereas 5% had hepatitis G virus coinfection and 15% had KSHV coinfection. A protective role for hepatitis G virus cannot be excluded but likely affects only a minority of HIV-1-infected African children.