Determining the prevalence of tuberculosis in emergency departments in the Eastern Cape region of South Africa and the utility of the World Health Organization tuberculosis screening tool

BACKGROUND

South Africa (SA) faces a significant tuberculosis (TB) burden complicated by high rates of HIV-TB co-infection. In SA, emergency departments (EDs) play an important role in screening for TB.

OBJECTIVES

To determine the prevalence of TB in the ED and the effectiveness of the World Health Organization (WHO) TB screening tool.

METHODS

This was a cross-sectional observational study, conducted in the ED at Livingstone Hospital, Port Elizabeth, from 4 June to 15 July 2018. All patients aged >18 years and able to consent were administered the WHO TB screening questions and underwent a point-of-care HIV test and demographic data collection. Patients were followed up for 1 year and tracked in the National Health Laboratory Service database to determine TB status using laboratory testing.

RESULTS

Over the study period, 790 patients were enrolled. Overall, 121 patients (15.3%) were TB-positive, with 46 (38.0%) diagnosed after presenting to the ED and 75 (62.0%) with a previous TB history determined by self-report or confirmed laboratory testing. A greater proportion of the TB-positive patients were HIV-positive (49.6%) compared with the TB-negative population (24.8%). TB-positive individuals were more likely to present to the ED with a chief complaint of shortness of breath (SoB) (18.2%) compared with the TB-negative population (10.5%). Overall, the WHO TB screening tool had poor sensitivity (46.5%) and specificity (62.5%) for identifying TB-positive patients in the ED. A multiple logistic regression analysis, controlled for age and sex, showed HIV status (odds ratio (OR) 2.81; p<0.001) and SoB (OR 2.19; p<0.05) to be significant predictors of TB positivity. Adding positive HIV status and a presenting complaint of SoB increased sensitivity to 78.3%.

CONCLUSIONS

EDs in SA face a high burden of TB. While WHO screening guidelines identify some of these patients, including routine HIV testing in the ED could significantly affect the number of TB diagnoses made.

Calibrating a chief complaint list for low resource settings: a methodologic case study

BACKGROUND

The chief or presenting complaint is the reason for seeking health care, often in the patient's own words. In limited resource settings, a diagnosis-based approach to quantifying burden of disease is not possible, partly due to limited availability of an established lexicon or coding system. Our group worked with colleagues from the African Federation of Emergency Medicine building on the existing literature to create a pilot symptom list representing an attempt to standardize undifferentiated chief complaints in emergency and acute care settings. An ideal list for any setting is one that strikes a balance between ease of use and length, while covering the vast majority of diseases with enough detail to permit epidemiologic surveillance and make informed decisions about resource needs.

METHODS

This study was incorporated as a part of a larger prospective observational study on human immunodeficiency virus testing in Emergency Departments in South Africa. The pilot symptom list was used for chief complaint coding in three Emergency Departments. Data was collected on 3357 patients using paper case report forms. Chief complaint terms were reviewed by two study team members to determine the frequency of concordance between the coded chief complaint term and the selected symptom(s) from the pilot symptom list.

RESULTS

Overall, 3537 patients' chief complaints were reviewed, of which 640 were identified as 'potential mismatches.' When considering the 191 confirmed mismatches (29.8%), the Delphi process identified 6 (3.1%) false mismatches and 185 (96.9%) true mismatches. Significant chief-complaint clustering was identified with 9 sets of complaints frequently selected together for the same patient. "Pain" was used 2076 times for 58.7% of all patients. A combination of user feedback and expert-panel modified Delphi analysis of mismatched complaints and clustered complaints resulted in several substantial changes to the pilot symptom list.

CONCLUSIONS

This study presented a systematic methodology for calibrating a chief complaint list for the local context. Our revised list removed/reworded symptoms that frequently clustered together or were misinterpreted by health professionals. Recommendations for additions, modifications, and/or deletions from the pilot chief complaint list we believe will improve the functionality of the list in low resource environments.

Tolerability and safety of mercaptopurine in azathioprine-intolerant patients with inflammatory bowel disease

BACKGROUND

Azathioprine intolerance is a common clinical problem, requiring drug withdrawal in up to 30% of patients. The successful use of mercaptopurine is described, but data to support this strategy are needed.

AIMS

To assess the tolerability of mercaptopurine in inflammatory bowel disease patients previously intolerant of azathioprine, and identify predictive factors.

METHODS

Sixty-one azathioprine-intolerant patients (31 males, median age at diagnosis 32 years, 31 with Crohn's disease, 30 with ulcerative colitis) who had been treated with mercaptopurine were identified. Intolerances included nausea and vomiting, flu-like illness, neutropenia, hepatotoxicity and pancreatitis.

RESULTS

Mercaptopurine was tolerated by 59% (36 of 61) of azathioprine-intolerant patients (median dose 1.0 mg/kg), 61% (17 of 28) in patients with azathioprine-related nausea and vomiting, 61% (11 of 18) with flu-like illness, 33% (three of nine) with hepatotoxicity, 100% (one of one) with neutropenia, 100% (three of three) with rash and 0% (zero of one) with pancreatitis. Mercaptopurine intolerance was frequently for a different adverse event. Those intolerant of mercaptopurine were younger (28.4 years vs. 37.0 years; P = 0.014) and more frequently female (14/30 vs. 2/29, P = 0.027). Mercaptopurine tolerability was not affected by diagnosis, location, behaviour, surgery, smoking, family history or extra-intestinal manifestations.

CONCLUSION

Mercaptopurine may be tolerated in up to 60% of azathioprine-intolerant patients, and treatment should be considered, particularly if intolerance was due to nausea, vomiting, flu-like illness or rash.

An immune control model for viral replication in the CNS during presymptomatic HIV infection

The brain is targeted by human immunodeficiency virus type 1 (HIV-1) during the course of untreated infection, leading to cognitive impairment, neurological damage and HIV encephalitis (HIVE). To study early dynamics of HIV entry into the brain, we examined a unique autopsy series of samples obtained from 15 untreated individuals who died in the presymptomatic stages of infection from non-HIV causes. HIV was detected and quantified by limiting dilution PCR and genetically characterized in the V3 region of env. Limiting dilution was shown to be essential for correct estimation of genetic partitioning between brain- and lymphoid-associated HIV populations. While no actively expressing HIV-infected cells were detected by immunohistochemistry, variable and generally extremely low levels of proviral DNA were detected in presymptomatic brain samples. V3 region sequences were frequently genetically distinct from lymphoid-associated HIV variants, with association index (AI) values similar to those observed in cases of HIVE. Infiltration of CD8 lymphocytes in the brain was strongly associated with expression of activation markers (MHCII; R = 0.619; P < 0.05), the presence of HIV-infected cells (proviral load; R = 0.608; P < 0.05) and genetic segregation of brain variants from populations in lymphoid tissue (AI value, R = -0.528; P approximately 0.05). CD8 lymphocytes may thus limit replication of HIV seeded into the brain in early stages of infection. Neurological complications in AIDS occur when this control breaks down, due to systemic immunosuppression from HIV that destroys CD8 lymphocyte function and/or through the evolution of more aggressive neuropathogenic variants.