Pneumocystis carinii is not a major cause of pneumonia in HIV infected patients in Lusaka, Zambia

The Burden of Pneumocystis Pneumonia Infection among HIV Patients in Ethiopia: A Systematic Review

Pneumocystis pneumonia (PCP) is a leading cause of death among patients with AIDS worldwide, but its burden is difficult to estimate in low- and middle-income countries, including Ethiopia. This systematic review aimed to estimate the pooled prevalence of PCP in Ethiopia, the second most densely populated African country. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were used to review published and unpublished studies conducted in Ethiopia. Studies that reported on the prevalence of PCP among HIV-infected patients were searched systematically. Variations between the studies were assessed by using forest plot and I-squared heterogeneity tests. Subgroup and sensitivity analyses were carried out when I2 > 50. The pooled estimate prevalence with 95% CI was computed using a random-effects model of analysis. Thirteen articles, comprising studies of 4847 individuals living with HIV, were included for analysis. The pooled prevalence of PCP was 5.65% (95% CI [3.74-7.56]) with high heterogeneity (I2 = 93.6%, p < 0.01). To identify the source of heterogeneity, subgroup analyses were conducted by study design, geographical region, diagnosis methods, and year of publication. PCP prevalence differed significantly when biological diagnostic methods were used (32.25%), in studies published before 2010 (32.51%), in cross-sectional studies (8.08%), and in Addis Ababa (14.05%). PCP prevalence differences of 3.25%, 3.07%, 3.23%, and 2.29% were recorded in studies based on clinical records, published since 2017, follow-up studies, and north-west Ethiopian studies, respectively. The prevalence of PCP is probably underestimated, as the reports were mainly based on clinical records. An expansion of biological diagnostic methods could make it possible to estimate the exact burden of PCP in Ethiopia.

Aetiology and prognosis of community-acquired pneumonia at the Adult University Teaching Hospital in Zambia

Background

Community-acquired pneumonia (CAP) is a frequent cause of death worldwide, and in sub-Saharan Africa particularly. Human immunodeficiency virus infection (HIV) and tuberculosis (TB) influence pathogen distribution in patients with CAP. Previous studies in sub-Saharan Africa have shown different frequencies of respiratory pathogens and antibiotic susceptibility compared to studies outside Africa. This study aimed to investigate the aetiology, presentation, and treatment outcomes of community-acquired pneumonia in adults at the University Teaching Hospital in Lusaka, Zambia.

Materials and methods

Three-hundred-and-twenty-seven patients were enrolled at the University Teaching Hospital in Lusaka between March 2018 and December 2018. Clinical characteristics and laboratory data were collected. Sputum samples were tested by microscopy, other TB diagnostics, and bacterial cultures.

Results

The commonest presenting complaint was cough (96%), followed by chest pain (60.6%), fever (59.3%), and breathlessness (58.4%). The most common finding on auscultation of the lungs was chest crackles (51.7%). Seventy percent of the study participants had complaints lasting at least a week before enrolment. The prevalence of HIV was 71%. Sputum samples were tested for 286 patients. The diagnostic yield was 59%. The most common isolate was Mycobacterium tuberculosis (20%), followed by Candida species (18%), Klebsiella pneumoniae (12%), and Pseudomonas aeruginosa (7%). Streptococcus pneumoniae was isolated in only four patients. There were no statistically significant differences between the rates of specific pathogens identified in HIV-infected patients compared with the HIV-uninfected. Thirty-day mortality was 30%. Patients with TB had higher 30-day mortality than patients without TB (p = 0.047).

Conclusion

Mycobacterium tuberculosis was the most common cause of CAP isolated in adults at the University Teaching Hospital in Lusaka, Zambia. Gram-negative organisms were frequently isolated. A high mortality rate was observed, as 30% of the followed-up study population had died after 30 days.

Prevalence of Pneumocystosis in Sub-Saharan Africa and Helminth Immune Modulation

Sub-Saharan Africa is the region of the world with the highest prevalence of helminth infections. To protect themselves from the defensive mechanisms of their respective hosts, helminths modulate their immune responses. This modulation has relevant clinical and epidemiological consequences, including the inhibition of inflammatory processes that characterize infection by other microorganisms. Severe Pneumocystis pneumonia is characterized by an intense inflammatory reaction that can lead to death. Acquired immunodeficiency syndrome is the main predisposing factor to the development of pneumocystosis. Although the introduction of highly active antiretroviral therapy has led to a notable decline in the incidence of acquired immunodeficiency syndrome-associated complications, pneumocystosis continues to be an important global health problem. Despite the high incidence of human immunodeficiency virus infection in the sub-Saharan region, the prevalence of Pneumocystis pneumonia there has been lower than expected. Several factors, or combinations thereof, may contribute to this evolution. Here, we hypothesize the possible role of helminth immune modulation as an important issue at play. On the other hand, and looking ahead, we believe that the immune modulation achieved by helminths may be an important factor to consider during the design and evaluation processes of vaccines against Pneumocystis jirovecii to be used in Sub-Saharan Africa. The requirements of a balanced triggering of different types of immune responses for controlling the infection produced by this microorganism, as observed during experiments in animal models, support this final consideration.

The Changing Epidemiology of Invasive Fungal Infections

Invasive fungal infections (IFI) are an emerging problem worldwide with invasive candidiasis and candidemia responsible for the majority of cases. This is predominantly driven by the widespread adoption of aggressive immunosuppressive therapy among certain patient populations (e.g., chemotherapy, transplants) and the increasing use of invasive devices such as central venous catheters (CVCs). The use of new immune modifying drugs has also opened up an entirely new spectrum of patients at risk of IFIs. While the epidemiology of candida infections has changed in the last decade, with a gradual shift from C. albicans to non-albicans candida (NAC) strains which may be less susceptible to azoles, these changes vary between hospitals and regions depending on the type of population risk factors and antifungal use. In certain parts of the world, the incidence of IFI is strongly linked to the prevalence of other disease conditions and the ecological niche for the organism; for instance cryptococcal and pneumocystis infections are particularly common in areas with a high prevalence of HIV disease. Poorly controlled diabetes is a major risk factor for invasive mould infections. Environmental factors and trauma also play a unique role in the epidemiology of mould infections, with well-described hospital outbreaks linked to the use of contaminated instruments and devices. Blastomycosis is associated with occupational exposure (e.g., forest rangers) and recreational activities (e.g., camping and fishing).The true burden of IFI is probably an underestimate because of the absence of reliable diagnostics and lack of universal application. For example, the sensitivity of most blood culture systems for detecting candida is typically 50 %. The advent of new technology including molecular techniques such as 18S ribosomal RNA PCR and genome sequencing is leading to an improved understanding of the epidemiology of the less common mould and dimorphic fungal infections. Molecular techniques are also providing a platform for improved diagnosis and management of IFI.Many factors affect mortality in IFI, not least the underlying medical condition, choice of therapy, and the ability to achieve early source control. For instance, mortality due to pneumocystis pneumonia in HIV-seronegative individuals is now higher than in seropositive patients. Of significant concern is the progressive increase in resistance to azoles and echinocandins among candida isolates, which appears to worsen the already significant mortality associated with invasive candidiasis. Mortality with mould infections approaches 50 % in most studies and varies depending on the site, underlying disease and the use of antifungal agents such as echinocandins and voriconazole. Nevertheless, mortality for most IFIs has generally fallen with advances in medical technology, improved care of CVCs, improved diagnostics, and more effective preemptive therapy and prophylaxis.

Burden of pneumocystis pneumonia in HIV-infected adults in sub-Saharan Africa: a systematic review and meta-analysis

Background

Seroprevalence data and clinical studies in children suggest that the burden of pneumocystis pneumonia (PCP) in Africa may be underestimated. We performed a systematic review to determine the prevalence and attributable mortality of PCP amongst HIV-infected adults in sub-Saharan Africa.

Methods

We searched Pubmed, Web of Science, Africa-Wide: NiPAD and CINAHL, from Jan 1 1995 to June 1 2015, for studies that reported the prevalence, mortality or case fatality of PCP in HIV-infected adults living in sub-Saharan African countries. Prevalence data from individual studies were combined by random-effects meta-analysis according to the Mantel-Haenszel method. Data were stratified by clinical setting, diagnostic method, and study year.

Results

We included 48 unique study populations comprising 6884 individuals from 18 countries in sub-Saharan Africa. The pooled prevalence of PCP among 6018 patients from all clinical settings was 15 · 4 % (95 % CI 12 · 9–18 · 0), and was highest amongst inpatients, 22 · 4 % (95 % CI 17 · 2–27 · 7). More cases were identified by bronchoalveolar lavage, 21 · 0 % (15 · 0–27 · 0), compared with expectorated, 7 · 7 % (4 · 4–11 · 1), or induced sputum, 11 · 7 % (4 · 9–18 · 4). Polymerase chain reaction (PCR) was used in 14 studies (n = 1686). There was a trend of decreasing PCP prevalence amongst inpatients over time, from 28 % (21–34) in the 1990s to 9 % (8–10) after 2005. The case fatality rate was 18 · 8 % (11 · 0–26 · 5), and PCP accounted for 6 · 5 % (3 · 7–9 · 3) of study deaths.

Conclusions

PCP is an important opportunistic infection amongst HIV-infected adults in sub-Saharan Africa, particularly amongst patients admitted to hospital. Although prevalence appears to be decreasing, improved access to antiretroviral therapy and non-invasive diagnostics, such as PCR, are needed.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1809-3) contains supplementary material, which is available to authorized users.

[Pneumocystis pneumonia biological diagnosis at Fann Teaching Hospital in Dakar, Senegal]

BACKGROUND

Data relative to Pneumocystis pneumonia in sub-Saharan Africa are not well known. Weakness of the technical material and use of little sensitive biological tools of diagnosis are among the evoked reasons. The objective of this study is to update the data of the disease at the Fann Teaching Hospital in Dakar and to estimate biological methods used in diagnosis.

MATERIALS AND METHODS

A descriptive longitudinal study was carried out from January 5th, 2009 to October 31st, 2011 in the parasitology and mycology laboratory of the Fann Teaching Hospital in Dakar. The bronchoalveolar lavages received in the laboratory were examined microscopically for Pneumocystis jirovecii by indirect fluorescent assay or after Giemsa or toluidine blue O staining.

RESULTS

One hundred and eighty-three bronchoalveolar lavages withdrawn from 183 patients were received in the laboratory. Sixteen were positive for P. jirovecii at 9% frequency. Four among these patients were HIV positive. Indirect fluorescent assay allowed finding of P. jirovecii among 16 patients while Giemsa staining discovered P. jirovecii only in a single patient. No case was diagnosed by toluidine blue O staining.

CONCLUSION

Pneumocystis pneumonia in Parasitology and Mycology Laboratory of Fann Teaching Hospital at Dakar was mainly diagnosed among HIV patients.

Co-infection of Mycobacterium tuberculosis and Pneumocystis jirovecii in the Iranian Patients With Human Immunodeficiency Virus

Background:

Based on the authors’ knowledge, there is no study on the co-infection of opportunistic agents such as Mycobacterium tuberculosis and Pneumocystis jirovecii in the lungs of Iranian patients with immunosuppression.

Objectives:

The current study aimed to show the rate of co-infection of M. tuberculosis and P. jirovecii in patients with Human Immunodeficiency Virus (HIV).

Patients and Methods:

Forty-five pulmonary samples were collected from 30 patients with HIV who also infected with Tuberculosis and Pneumonia. All of the patients were admitted to two university hospitals of Mycobacteriology and the Iranian HIV/AIDS research centers. DNA of P. jirovecii was detected using nested-Polymerase Chain Reaction (nested-PCR) assay.

Results:

All of the patients were male with the mean age of 32.95 ± 7.15 years. The mean of CD4 cell count was 109.25 cell/mm³. Of 30 patients with HIV, three (10%) were co-infected with M. tuberculosis and P. jirovecii. No other causes of pneumonia were found in those three patients and CD4 cell counts less than 50 cell/mm³ was reported.

Conclusions:

The results of the current study showed a high rate of co-infection of M. tuberculosis and P. jirovecii in the Iranian patients with HIV. As the immune system condition worsened, the probability of occurrence of Pneumocystis Pneumonia (PCP) increased. Therefore, more specific, most rapid and sensitive tests should be utilized for diagnosis of PCP in this group of patients.

Burden of pneumocystis pneumonia in HIV-infected adults in sub-Saharan Africa: protocol for a systematic review

BACKGROUND

Reports from Africa have suggested that pneumocystis pneumonia (PCP) is a less important cause of morbidity than in the developed world. However, more recent studies have shown high seroprevalence rates of P. jirovecii in healthy individuals with HIV as well as high rates of clinical disease in African children. This suggests that PCP may be more common in Africa than was previously recognised. Understanding the contribution of PCP to disease in HIV-infected individuals in sub-Saharan Africa (SSA) has important implications for diagnosis, management and resource allocation. We therefore propose to conduct a systematic review and meta-analysis in order to investigate the burden of PCP in this population.

METHODS AND DESIGN

We plan to search electronic databases and reference lists of relevant articles published from 1995 to May 2013 using broad terms for pneumocystis, HIV/AIDS and sub-Saharan Africa. Studies will be included if they provide clear diagnostic criteria for PCP and well-defined study populations or mortality data (denominator). A novel quality score assessment tool has been developed to ensure fidelity to inclusion criteria, minimise risk of selection bias between reviewers and to assess quality of outcome ascertainment. This will be applied to eligible full-text articles. We will extract data using a standardised form and perform descriptive and quantitative analysis to assess PCP prevalence, mortality and case fatality, as well as the quality of included studies. This review protocol has been published in the PROSPERO International Prospective Register of systematic reviews, registration number CRD42013005530.

DISCUSSION

Our planned review will contribute to the diagnosis and management of community-acquired pneumonia in HIV-infected individuals in SSA by systematically assessing the burden of PCP in this population. We also describe a novel quality assessment tool that may be applied to other prevalence reviews.

Pneumocystis jirovecii pneumonia in developing countries

Pneumocystis pneumonia (PcP) is a serious fungal infection among immunocompromised patients. In developed countries, the epidemiology and clinical spectrum of PcP have been clearly defined and well documented. However, in most developing countries, relatively little is known about the prevalence of pneumocystosis. Several articles covering African, Asian and American countries were reviewed in the present study. PcP was identified as a frequent opportunistic infection in AIDS patients from different geographic regions. A trend to an increasing rate of PcP was apparent in developing countries from 2002 to 2010.

Pneumocystis jiroveci pneumonia and other pulmonary infections in TB smear-negative HIV-positive patients with atypical chest X-ray in Ethiopia

Pneumocystis pneumonia (PCP) has been considered a rare disease in sub-Saharan Africa. However, a rising prevalence has been noted recently. The objective of this study was to determine the relative prevalence of PCP and other pulmonary opportunistic diseases in patients infected with HIV in Ethiopia. 131 consecutive patients with respiratory symptoms and atypical chest X-ray, who were sputum smear-negative for AFB and seroreactive for HIV, underwent clinical evaluation and investigation for Pneumocystis jiroveci and Mycobacterium tuberculosis from sputum and bronchoalveolar lavage (BAL), and fungal and bacterial pathogens from BAL alone. Bacterial infections, Pneumocystis pneumonia (PCP) and pulmonary tuberculosis (PTB) occurred in 44 (33.6%), 39 (29.7%) and 31 (23.7%) patients, respectively. Pulmonary Kaposi sarcoma and non-specific interstitial pneumonitis occurred in 4 patients each. In a multivariate regression model, predictors of PCP were typical chest X-ray and low CD4 count while purulent sputum predicted bacterial infection. The sensitivity of physicians and chest X-ray diagnosis was particularly low for PTB and bacterial infections. We conclude that chronic bacterial infection and Pneumocystis pneumonia are important differential diagnoses in HIV-infected, smear-negative PTB patients presenting with atypical chest X-ray. We therefore need to escalate the use of preventive and highly active antiretroviral (HAART) treatment in order to prevent a PCP epidemic.

Low sensitivity of a nested polymerase chain reaction in oropharyngeal washings for the diagnosis of pneumocystis pneumonia in HIV-infected patients

STUDY OBJECTIVE

To compare the relative yield and diagnostic utility of the polymerase chain reaction (PCR) analysis for Pneumocystis jirovecii DNA in oropharyngeal washings using transbronchial biopsy (TBBx) and BAL as "gold standards."

DESIGN

Prospective study.

SETTING

Academic tertiary center.

PATIENTS

Oropharyngeal washes were obtained in 50 consecutive patients with clinical pneumocystis pneumonia (PCP). Because of varying clinical severity, not all patients tolerated bronchoscopy. Thirty-five patients underwent TBBx, and 48 patients underwent BAL.

METHODS

DNA extracted from oropharyngeal washings and BAL was subjected to a nested PCR test using primers for the large subunit mitochondrial ribosomal RNA of P jirovecii. Oropharyngeal washings were compared with BAL PCR and TBBx.

RESULTS

Sixteen of the 35 TBBx procedures had positive results for PCP (46%). Oropharyngeal washings yielded positive results for pneumocystis in 7 of the 16 patients (sensitivity, 44%; specificity, 79%). Thirty-five of 48 patients (73%) had positive PCR results on BAL analysis. The relative yield of the PCR in oropharyngeal washes compared with BAL fluid was 40% (14 of 35 washes), giving a sensitivity of 40% and specificity of 77%.

CONCLUSION

PCR DNA amplification of oropharyngeal washings in HIV-seropositive subjects has a low sensitivity and specificity for the diagnosis of PCP.

Efficacy and safety of two dosages of cotrimoxazole as preventive treatment for HIV-infected Malawian adults with new smear-positive tuberculosis

OBJECTIVE

To assess the efficacy and safety of two different dosages of cotrimoxazole (CTX) in prophylaxis in HIV-positive new smear-positive pulmonary tuberculosis (TB) patients in Blantyre, Malawi.

METHOD

Randomized, double-blind trial using 480 and 960 mg of CTX given to new TB patients, who were followed up until the end of the tuberculosis treatment. The primary outcome was survival. The outcome in the two groups was also compared with an unselected cohort of similar patients registered in Zomba, Malawi in 1995 and new smear-positive patients registered in the National Tuberculosis Programme in 1999. The secondary outcome was the occurrence of (opportunistic) events, especially bacterial pneumonia.

RESULTS

There were no statistically significant differences in mortality and bacterial pneumonia between the groups receiving the two different dosages. The case fatality rate at the end of the tuberculosis treatment was 15.4% in the 480 mg group and 14.0% in the 960 mg group. This was lower than the case fatality rate in the Zomba cohort (19.2%, P = 0.10) and lower than the case fatality rate in the national programme (21.0%, P < 0.001). CTX was well tolerated. Compliance was fair.

CONCLUSIONS

CTX prophylaxis may have a beneficial effect on mortality and morbidity in HIV-infected smear-positive tuberculosis patients in Malawi. The efficacy of both dosages is not significantly different. The intervention is cheap and easy to implement. These results would support implementation of CTX in this patient group until better strategies are available or evidence is convincingly presented to suggest that its benefit is marginal.

Predictors of HIV serostatus among HIV discordant couples in Lusaka, Zambia and female antenatal clinic attendants in Kigali, Rwanda

Clinical manifestations of HIV disease in Africa are nonspecific and easily confused with other endemic diseases. Several studies have compared the prevalence of HIV-related signs and symptoms in infected versus uninfected populations, but little is known about differences in HIV disease manifestations between African men and women across geographic areas. We conducted a cross-sectional study to define predictors of HIV status and assess their differences by gender and country in two African cohorts: 1351 heterosexual couples recruited from a voluntary HIV counseling and testing center in Lusaka, Zambia, and 1458 women recruited from antenatal and pediatric clinics in Kigali, Rwanda. HIV-positive Zambian men and women differed most with respect to prevalence of wasting syndrome (48.1% vs. 35.5%, p < 0.01). Zambian women were more likely to have a disseminated adenopathy than Rwandan women (33.2% vs. 7.8%, p < 0.01) and had a much higher median erythrocyte sedimentation rate (ESR) than either of the two other groups (78 mm/hr vs. 47 mm/hr, p < 0.01). Multivariable logistic regression modeling showed a history of tuberculosis [odds ratio (OR): 2.8-20.7], adenopathy on examination (OR: 4.0-6.3), and an ESR of >65 mm/hr (OR: 3.1-5.9) to be strongly predictive of HIV status in all groups. These screening tools, though highly predictive of HIV infection, were insensitive, as most infected persons were asymptomatic. Given these differences in HIV disease manifestation, screening tools based on signs and symptoms should be adapted accordingly. Additional studies are required to evaluate clinical markers as predictors of HIV disease progression and adjust them according to regional and gender differences.

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.

Identification of Pneumocystis carinii DNA in oropharyngeal mouth washes from AIDS children dying of respiratory illnesses

Polymerase chain reaction (PCR) using Pneumocystis carinii-specific primers pAZ 102-H(5'-GTGTACGTTGCAAAGTACTC-3') and pAZ 102-E(5'-GATGGCTGTTTCCAAGCCCA-3') was performed on oropharyngeal washes obtained at autopsy from 22 AIDS children with histologically confirmed P. carinii pneumonia (PCP), and 48 control AIDS children who died from other infections. Fifteen of 22 (68%) PCP samples and none of 48 (0%) control samples had detectable P. carinii DNA (sensitivity 68%; specificity 100%; positive predictive value 100%; negative predictive value 87%). This method requires further validation in clinical practice.

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).

Fatal Pneumocystis carinii pneumonia in HIV-seropositive infants in Harare, Zimbabwe

Lung biopsies taken post mortem from 24 HIV-seropositive children who died of pneumonia in Harare Hospital (Zimbabwe) during 1995 were examined for pathogens using histology, culture, microscopy and polymerase chain reaction (PCR). Pneumocystis carinii was detected in 16 (67%) children, in 5 of whom bacterial pathogens were also detected. There were 2 cases of cytomegalovirus infection. On the basis of histology and PCR, none of the children had tuberculosis. These data add to the evidence that P. carinii pneumonia may be a significant cause of death in HIV-infected children in southern Africa. Policies on treatment for severe pneumonia, and on prophylaxis for children born to HIV-seropositive mothers need to be re-examined.

Culture-positive tuberculosis in human immunodeficiency virus type 1-infected children

BACKGROUND

Adults infected by HIV have increased susceptibility to Mycobacterium tuberculosis and progress more rapidly to disease. HIV and tuberculosis (TB) coinfection in children has been reported but often lacks bacterial confirmation. We report on the clinical picture, special investigations, clinical course and outcome of 14 children with HIV infection and culture-confirmed TB from a developing country.

METHODS

The clinical records of all children, from 1992 to 1997, with HIV infection and culture-proved TB were reviewed.

RESULTS

Fourteen (10.4%) of 135 children with vertically transmitted HIV infection, 93% <2 years of age, fit the criteria. Nonresolving pneumonia (4) and otorrhoea (6) were common complaints. A Mantoux test was positive (> or =15 mm) in 6 of 11 children. Extrapulmonary TB was present in 5 cases. Ear swabs were the source of M. tuberculosis culture in 3. Chest radiographs were abnormal in all with hilar and paratracheal lymphadenopathy present in 7. A source case with pulmonary TB was identified for 10. Susceptibility tests were done on 9 strains of which 1 was drug-resistant. Four children were culture-positive 4 to 10 months after initiation of TB treatment. Mortality was 21% and 3 were lost to follow-up.

CONCLUSIONS

In HIV-infected children the Mantoux skin test remains useful and culture specimens should be obtained from all sources. Response to treatment is unpredictable, and for this reason repeated cultures should be taken during treatment and a 9-month course of treatment considered.

Treatment outcome of an unselected cohort of tuberculosis patients in relation to human immunodeficiency virus serostatus in Zomba Hospital, Malawi

There is little information about treatment outcome in patients with smear-negative pulmonary tuberculosis (PTB) or extrapulmonary tuberculosis (EPTB) treated under routine programme conditions in subsaharan Africa. A prospective study was carried out to determine treatment outcome in an unselected cohort of TB patients admitted to Zomba General Hospital, Malawi. Eight hundred and twenty-seven adult TB patients (451 men and 376 women) were registered between 1 July and 31 December 1995. Standardized treatment outcomes of treatment completion, death, default, and transfer to another district were assessed in relation to type of TB, human immunodeficiency virus (HIV) serostatus, age and gender. Two hundred and fifty-four patients (31%) died by the end of treatment, half of the deaths occurring in the first month. Death rates were 19% among 386 patients with smear-positive PTB, 46% among 211 patients with smear-negative PTB, and 37% among 230 patients with EPTB; 77% of the patients were HIV seropositive. Among new patients, HIV-positive patients had higher death rates than HIV-negative patients (hazard ratio [HR] 2.5; 95% confidence interval [95% CI] 1.6-3.8). Smear-negative patients had the highest death rates (HR 3.9; 95% CI 2.7-5.5 compared to smear-positive patients), followed by EPTB patients (HR 2.6, 95% CI 1.8-3.7 compared to smear-positive patients). Death rates increased with age but were similar in men and women. Adult patients in Malawi with smear-negative PTB and EPTB have low treatment completion and high death rates, related to high levels of HIV infection. National TB control programmes in areas of high HIV prevalence should no longer ignore treatment outcomes in patients with smear-negative PTB or EPTB.

Pneumocystis carinii pneumonia in Malawian children

Sixty children aged between 1 and 23 months admitted to Queen Elizabeth Central Hospital in Blantyre, Malawi for diagnosis of acute lower respiratory tract infections (ALRI) were investigated for laboratory diagnosis of Pneumocystis carinii pneumonia (PCP) by indirect immunofluorescence assay on nasopharyngeal secretions. P. carinii was found in five of the 60 children. Three PCP cases had AIDS. The clinical presentation of children with PCP was of little diagnostic value and all the children were infants. Arterial oxygen saturation was significantly lower in PCP cases. Of the five PCP cases, four died, indicating that the marked hypoxaemia was associated with poor prognosis. These results indicate that an immunofluorescence assay on nasopharyngeal secretions could be used for first-line diagnosis of PCP in Africa.

Tuberculosis in Africa: clinical presentation and management

In the last decade, sub-Saharan Africa has experienced an explosive increase in tuberculosis (TB) cases, largely as a result of the co-epidemic of human immunodeficiency virus (HIV) infection. This article reviews the essential background epidemiology of TB in sub-Saharan Africa. The clinical features and diagnostic problems of pulmonary/extrapulmonary TB in adults and children are discussed, particularly in relation to HIV infection. Different treatment regimens, their cost, adverse reactions, the ways in which HIV infection influences treatment response and the extent of drug resistance are reviewed. The recommended approaches to TB control in Africa, including methods used to prevent TB through Bacillus Calmette-Guerin and chemoprophylaxis are examined. The success achieved by good National TB Control Programmes in some African countries allows cautious optimism that this epidemic can be controlled.

Pneumocystis carinii and cytomegalovirus infections in severely ill, HIV-infected African infants

Unlike in the industrialized world, in which Pneumocystis carinii and cytomegalovirus (CMV) are major respiratory opportunistic organisms, the causes of severe pneumonia, which accounts for much of the mortality in HIV-infected infants in developing countries, are not known, although tuberculosis has been associated with HIV in adults. We report on post-mortem lung and liver biopsies obtained soon after death from 36 HIV-infected infants and 36 HIV-uninfected matched controls who had been admitted with severe pneumonia to an ICU. Nineteen of the HIV-infected infants were classified by WHO criteria as having AIDS and 17 'symptomatic HIV'. P. carinii and CMV were detected significantly more frequently in lung tissue from the AIDS patients (14 of 18 samples tested, p < 0.01; 14 of 18 samples tested, p < 0.01, respectively) as compared with matched controls. P. carinii was detected in two of 13 lung biopsies from symptomatic HIV infants, but in none of the controls. Lung tissue obtained from AIDS patients had P. carinii and CMV more frequently (p < 0.01, p < 0.01, respectively) than that from symptomatic HIV patients. CMV was also detected in excess in liver tissue from AIDS infants (five of 18 samples) as compared with that from symptomatic HIV (0 of 16; p = 0.03) and matched controls (two of 34; p = 0.04). Ante-mortem investigations revealed more CMV infections in AIDS patients (four of 19) than in matched controls (0 of 36; p < 0.01). Tuberculosis was detected in post-mortem lung tissue from only one patient with symptomatic HIV infection. The finding that pathogens (P. carinii, CMV) most frequently detected in seriously ill African infants with HIV/AIDS are similar to those in their counterparts from industrialized countries has implications for improved management in the former.

Prospective, controlled study of the outcome of human immunodeficiency virus-1 antibody-positive children admitted to an intensive care unit

OBJECTIVE

Intensive care resources are both scarce and costly in South Africa. We set out to ascertain whether human immunodeficiency virus (HIV) status affects the spectrum of disease and the prognosis in children treated in pediatric intensive care units (ICUs).

DESIGN

A prospective, case-controlled study.

SETTING

The pediatric ICU at Kind Edward VIII Hospital, Durban, South Africa.

PATIENTS

HIV-positive cases were classified as "acquired immunodeficiency syndrome," "symptomatic HIV," and "HIV-unrelated diseases." Controls were matched for age, race, gender, severity of disease, and admitting diagnosis.

MEASUREMENTS AND MAIN RESULTS

THe clinician was blinded to the serostatus of patients. Informed consent and Ethics Committee approval were obtained for HIV testing and the study. Outcome measures were the duration of intermittent positive-pressure ventilation and ICU stay, maximum ventilatory requirements, infectious complications, and mortality. There were 11 cases of acquired immune deficiency (AIDS), 24 cases of symptomatic HIV, and 13 cases of HIV-unrelated diseases. Mortality rates for the three groups were as follows: 100% in patients with AIDS compared with 55% in their controls (p<.01); 38% in patients with symptomatic HIV and 46% in controls. Cytomegalovirus and Pneumocystis carinii infections were significantly increased (p<.01, p<.002, respectively) in patients with AIDS as compared with controls. Outcome measures were similar in those patients with symptomatic HIV and those patients with HIV-unrelated diseases, as compared with their respective controls.

CONCLUSIONS

Outcome in children with AIDS admitted to the pediatric ICU was significantly worse than the outcome in HIV-uninfected children. However, the number of AIDS patients studied was small. HIV antibody-positive children without AIDS do as well as uninfected controls. Ethics committees in resource-constrained countries may be assisted by such data when making difficult decisions on the admissions of HIV-infected patients to pediatric ICU facilities.

Pneumocystis carinii pneumonia in Zimbabwe

Pneumocystis carinii pneumonia (PCP) is said to be rare in Africa, with reported rates of 0-22% in human-immunodeficiency-virus (HIV) infected individuals with respiratory symptoms. Over one year in a central hospital in southern Africa, 64 HIV-infected patients with acute diffuse pneumonia unresponsive to penicillin and sputum smear-negative for acid-fast bacilli underwent fibreoptic bronchoscopy. Bronchoalveolar lavage fluid was assessed for bacteria, fungi, Pneumocystis carinii, and mycobacteria. 21 patients (33%) had PCP and 24 (39%) had tuberculosis; 6 of these had both infections. 5 patients had Kaposi's sarcoma (KS) associated with PCP, tuberculosis, or another infection, in 1 patient KS was the only finding, and in 21 no pathogen was identified. A logistic regression model was used to assess clinical, radiographic, and arterial blood gas predictors of PCP and tuberculosis. Fine reticulonodular shadowing on the chest radiograph (nodular component < 1 mm) was the strongest independent predictor of PCP (odds ratio 8.5 [95% CI 6.1-10.9]). A respiratory rate of more than 40/min was the best clinical predictor of PCP (odds ratio 11.2 [95% CI 8.8-13.6]). Median CD4+ T cell count for all cases of PCP was 134/microL (range 5-355) and for tuberculosis without PCP 206/microL (range 61-787). In resource-limited countries, a regionally appropriate management algorithm is required.

Pneumocystis carinii pneumonia in cancer patients

Concern has been arisen about the recently reported increasing incidence of PCP in patients with cancer and the potential transmissibility of this infection. Whether or not there is an increase in the incidence of P. carinii infections, PCP should be considered in the differential diagnosis of pulmonary infiltrates in bone marrow transplant recipients, in patients with hematologic neoplasms and in patients with primary or metastatic brain neoplasms. Intensity of immunosuppression plays a crucial role, especially long-term (> 2 months) corticosteroid treatment. PCP is usually manifested clinically during augmentation or during tapering of corticosteroid dose. Thus, if the chest radiograph of a high-risk patient shows diffuse infiltrates, bronchoscopy and bronchoalveolar lavage should be done immediately. Treatment options are the same as for the AIDS population, except that TMP-SMX is tolerated better in non-AIDS patients. The role of supportive care, including mechanical ventilation in such patients should not be underestimated. Oral therapy with dapsone-trimethoprim or with atovaquone, can be as effective as conventional therapy in mild disease, permitting treatment on an outpatient basis. PCP is often preventable and our understanding has improved about when prophylaxis should be initiated. In the future, the emergence of new technologies for diagnosis and of new agents for treatment and prophylaxis, will bring us closer to the goal of controlling this serious infection.

Is Pneumocystis carinii a deep mycosis-like agent?

Pneumocystis carinii is a widespread eukaryotic microorganism found in the lungs of healthy mammals, including humans. It is able to proliferate extensively in the alveoli, becoming an important agent of severe pneumonitis in immunosuppressed hosts, especially in persons suffering from AIDS. The taxonomic position of P. carinii is uncertain. Typical cytoplasmic organelles of eukaryotic cells have been found and described in the parasite. Biochemical research is hindered by the lack of an efficient in vitro culture system. Results of comparative study of nucleic acid sequences suggest that Pneumocystis is a fungus. However, ultrastructural, biochemical and nucleic acid homology insights appear as clearly insufficient to class Pneumocystis. Pneumocystis infection might be acquired, as deep mycoses, from environmental sources through the respiratory tract. Thus, the hypothesis of an environmental stage of the parasite must be considered. Pneumocystis might be seen as a widespread pathogenic dimorphous fungus. As fungal agents, P. carinii is able to disseminate from the infected lung to other organs. However, deep mycoses and pneumocystosis induce different histopathological changes in the host. Furthermore, deep fungal infections, unlike pneumocystosis, cannot be transmitted from one infested host to another one. Beside these two aspects, pneumocystosis shares many features with deep mycoses. Research on the epidemiology of pneumocystosis is needed.

Pneumocystis carinii pneumonia. An uncommon cause of death in African patients with acquired immunodeficiency syndrome

Admissions and deaths in a pulmonary medicine ward in Abidjan, Cote d'Ivoire, West Africa, were evaluated over a 6-month period in 1989 with systematic autopsies on all patients who died. Of 473 patients admitted, 38% were HIV-1 seropositive, 4% were HIV-2 seropositive, and 14% reacted to both viruses. A total of 100 patients (21%) died, and deaths were twice as frequent in HIV-seropositive compared with HIV-negative patients. The pathology of 78 autopsies showed that the predominant cause of death in HIV-seropositive patients was disseminated tuberculosis (40%). Cancer was the cause of death in 64% of HIV-negative patients. Pneumocystosis was found in only 9% of HIV-seropositive autopsies. Since Pneumocystis carinii is an uncommon cause of death in this population, prophylaxis for P. carinii pneumonia is not warranted for HIV-infected patients in Africa. In contrast, research on chemoprophylaxis for tuberculosis is urgently required.

Pneumocystis carinii, an opportunist in immunocompromised patients

Pneumocystis carinii has been recognized as a cause of pneumonia in immunocompromised patients for over 40 years. Until the 1980s, Pneumocystis pneumonia (pneumocystosis) was most often seen in patients undergoing chemotherapy for malignancy or transplantation. Infection could be prevented by trimethoprim-sulfamethoxazole prophylaxis; thus, it was an uncommon clinical problem. With the onset of the AIDS epidemic, Pneumocystis pneumonia has become a major problem in the United States because it develops in approximately 80% of patients with AIDS and because almost two-thirds of patients have adverse reactions to anti-Pneumocystis drugs. Thus, physicians and laboratories in any community may be called upon to diagnose and provide care for patients with Pneumocystis pneumonia. The classification of the organism is currently controversial, but it is either a protozoan or a fungus. P. carinii appears to be acquired during childhood by inhalation and does not cause clinical disease in healthy persons but remains latent. If the person becomes immunosuppressed, the latent infection may become activated and lead to clinical disease. Damage of type I pneumocytes by Pneumocystis organisms leads to the foamy alveolar exudate which is characteristic of the disease. Diagnosis is established by morphologic demonstration of Pneumocystis organisms in material from the lungs. Current efforts to find better anti-Pneumocystis drugs should provide more effective therapy and prophylaxis.

Legionellosis in patients with HIV infection

During the five-year period 1984-1988 we received 192 specimens from 180 patients infected with the human immunodeficiency virus (HIV) for investigation of Legionella infection. The majority of specimens were bronchoalveolar lavage (BAL) fluids (84%), but tracheal suctions and lung tissue from autopsies were also examined. The diagnostic methods used were a direct immunofluorescence assay (DFA) for the detection of Legionella antigen, and culture on buffered charcoal yeast extract (BCYE-alpha) media. All specimens were also examined for the presence of other bacterial lung pathogens, and all BAL specimens additionally for Pneumocystis carinii and mycobacteria. Legionellosis was not found to be common among HIV-infected patients, as only six specimens (3%) from six patients were found positive by DFA, and no specimens were culture-positive for Legionella species. Dual infection with Legionella and P. carinii occurred in two patients. Clinical data of the six patients are presented, and currently used methods for diagnosing legionellosis are discussed.

Infection with Pneumocystis carinii is prevalent in healthy Gambian children

Pneumocystis pneumonia is rarely identified in the many immunosuppressed individuals with acquired immune deficiency syndrome (AIDS) and malnutrition in Africa. To test whether infection with Pneumocystis carinii occurs in the continent we conducted a comparative serological study, measuring by enzyme-linked immunosorbent assay antibodies to the parasite in 150 healthy young individuals from both Britain and the Gambian savanna. The prevalence of significant titres of antibody to P. carinii steadily increased with age and included more than 70% of both populations by 8 years of age. Infection with P. carinii is, therefore, common in the Gambia. Thus opportunistic pneumocystis pneumonia may be an important but largely unrecognized disease in the continent, though its impact is probably diminished by the prevalence of fatal tuberculous infection, particularly in the AIDS population.

Opportunistic infections in AIDS in developed and developing countries

The acquired immune deficiency syndrome (AIDS) is fundamentally the same disease in all parts of the world, but the prevalence of microorganisms in an environment governs the patterns of disease arising from reactivated latent infections, invading pathogens and opportunistic infections. AIDS in Africa has certain characteristic presentations. Enteropathic AIDS is most common: Cryptosporidium and Isospora belli are identified in up to 60% of patients, but it is uncertain whether they are the causes of diarrhoea. Pneumocystis carinii pneumonia is rare. Tuberculosis, both pulmonary and extrapulmonary, is the supreme complicating infection. Herpes zoster is frequently the first clinical presentation, and has a 95% positive predictive value for HIV positivity. Measles may be more frequent in infants born to HIV-infected mothers, and appears to be worse in HIV-infected children. There is accelerated progress of both diseases in patients infected by HIV and Mycobacterium leprae. Salmonellosis is frequent. There is no direct interaction between malaria and HIV, but, by being a potent cause of anaemia, malaria enhances transmission of HIV to children through blood transfusion. HIV-positive subjects are liable to new or reactivated visceral leishmaniasis with dissemination to unusual sites. Cerebral toxoplasmosis is common. There are no apparent interactions between HIV and helminths, although there is one report of hyperinfection with Strongyloides stercoralis. Cryptococcal meningitis has high frequency. Infections with Histoplasma encapsulatum are common in tropical America, but there has been no increase of frequency of H. duboisii in Africa since the advent of AIDS.