Comparative performance characteristics of the urine lipoarabinomannan strip test and sputum smear microscopy in hospitalized HIV-infected patients with suspected tuberculosis in Harare, Zimbabwe

BackgroundIn Zimbabwe, sputum smear microscopy (SSM) is the routinely used TB diagnostic tool in hospitalised HIV-infected patients. However, SSM has poor sensitivity in HIV-infected patients. We compared performance of urine lipoarabinomannan strip test (LAM) and SSM among hospitalized HIV-infected patients with suspected TB.MethodsHospitalized HIV-infected patients with suspected TB were randomized to LAM plus SSM or SSM alone groups as part of a larger multi-country parent study. Here we present a comparison of LAM versus SSM performance from the Zimbabwe study site. LAM analyses (grade 2 cut-off) were conducted using (i) a microbiological reference standard (MRS; culture positivity for M.tb and designated definite TB) and (ii) a composite reference standard (CRS; definite TB plus probable TB i.e. patients with clinical TB excluded from the culture negative group). CRS constituted the primary analysis.Results82/457 (18%) of the patients randomized to the LAM group were M.tuberculosis culture positive. Using CRS, sensitivity (%, 95 % CI) of LAM was significantly higher than SSM [49.2 (42.1-56.4) versus 29.4(23.2-36.3); p 100 cells/μL. The combined sensitivity of LAM and SSM was higher than SSM alone being highest at CD4 counts 97% in all the 3 CD4 strata.ConclusionAmong hospitalized HIV-infected patients with suspected TB, the sensitivity of LAM is significantly higher than that of SSM, especially at low CD4 counts. LAM and SSM are complimentary tests for diagnosis of TB in HIV-infected patients. We recommend a combination of LAM and SSM for TB diagnosis in HIV-infected patients with low CD4 counts in HIV/TB co-endemic countries, where alternative methods are unavailable

An Optimal Diagnostic Strategy for Tuberculosis in Hospitalized HIV-Infected Patients Using GeneXpert MTB/RIF and Alere Determine TB LAM Ag.

The diagnosis of tuberculosis (TB) in HIV-infected patients is challenging. Both a urinary lipoarabinomannan (LAM) test (Alere TB LAM) and GeneXpert-MTB/RIF (Xpert) are useful for the diagnosis of TB. However, how to optimally integrate Xpert and LAM tests into clinical practice algorithms remain unclear. We performed a post hoc analysis of 561 HIV-infected sputum-expectorating patients (median CD4 count of 130 cells/ml) from a previously published randomized controlled trial evaluating the LAM test in hospitalized HIV-infected patients with suspected TB. We evaluated 5 different diagnostic strategies using sputum culture as a reference standard (Xpert alone, LAM alone, sequential Xpert followed by LAM and vice versa [LAM in Xpert-negative patients and Xpert in LAM-negative patients], and both tests concurrently [LAM + Xpert]). A cost-consequence analysis was performed. Strategy-specific sensitivity and specificity, using culture as a reference, were similar with the Xpert-only and sequential and concurrent strategies. However, when any positive TB-specific test was used as a reference, the incremental yield of LAM over Xpert was 29.6% (45/152) and that of Xpert over LAM was 75% (84/11). The incremental yield of LAM increased with decreasing CD4 count. The costs per TB case diagnosed were similar for the sequential and concurrent strategies ($1,617 to$1,626). In sputum-expectorating hospitalized patients with advanced HIV and access to both tests, concurrent testing with Xpert and LAM may be the best strategy for diagnosing TB. These data inform clinical practice in settings where TB and HIV are endemic

Diagnosing tuberculosis in hospitalized HIV-infected individuals who cannot produce sputum: is urine lipoarabinomannan testing the answer?

Abstract Background Up to one third of HIV-infected individuals with suspected TB are sputum-scarce. The Alere Determine™ TB LAM Ag lateral flow strip test can be used to diagnose TB in HIV-infected patients with advanced immunosuppression. However, how urine LAM testing should be incorporated into testing algorithms and in the context of specific patient sub-groups remains unclear. Methods This study represents a post hoc sub-group analysis of data from a randomized multi-center parent study. The study population consisted of hospitalized HIV-infected patients with suspected TB who were unable to produce sputum and who underwent urine LAM testing. The diagnostic utility of urine LAM for TB in this group was compared to the performance of urine LAM in patients who did produce a sputum sample in the parent study. Results There were a total of 187 and 2341 patients in the sputum-scarce and sputum-producing cohorts, respectively. 80 of the sputum-scarce patients underwent testing with urine LAM. In comparison to those who did produce sputum, sputum-scarce patients had a younger age, a lower Karnofsky performance score, and a lower weight and BMI at admission. A greater proportion of sputum-scarce patients were urine LAM positive, compared to those who were able to produce sputum (31% vs. 21%, p = 0.04). A higher proportion of sputum-scarce patients died within 8 weeks of admission (32% vs. 24%, p = 0.013). We inferred that 19% of HIV-infected sputum-scarce patients suspected of TB were diagnosed with tuberculosis by urine LAM testing, with an estimated positive predictive value of 63% (95% CI 43–82%). Conclusions Urine LAM testing can effectively identify tuberculosis in HIV-infected patients who are at a higher risk of mortality yet are unable to generate a sputum sample for diagnostic testing. Our findings support the use of urine LAM testing in sputum-scarce hospitalized HIV-infected patients, and its incorporation into diagnostic algorithms for this patient population

Low-dose amikacin in the treatment of Multidrug-resistant Tuberculosis (MDR-TB)

Abstract Background The World Health Organization recommends intravenous amikacin for the treatment of MDR-TB at a dose of 15 mg/kg. However, higher doses are associated with significant toxicity. Methods Patients with MDR-TB treated at our institution receive amikacin at 8–10 mg/kg, with dose adjustment based on therapeutic drug monitoring. We conducted a retrospective cohort study of patients with MDR-TB who received amikacin between 2010 and 2016. Results Forty-nine patients were included in the study. The median starting dose of amikacin was 8.9 mg/kg (IQR 8, 10), and target therapeutic drug levels were achieved at a median of 12 days (IQR 5, 26). The median duration of amikacin treatment was 7.2 months (IQR 5.7, 8), and median time to sputum culture conversion was 1 month (IQR 1,2). Six patients (12.2%) experienced hearing loss based on formal audiometry testing (95% CI 4.6–24.8%); 22.2% had subjective hearing loss (95% CI 11.2–37.1%) and 31.9% subjective tinnitus (95% CI 19.1–47.1%). Ten patients (23%) had a significant rise in serum creatinine (95% CI 11.8–38.6%), but only 5 patients had a GFR < 60 at treatment completion. 84% of patients had a successful treatment outcome (95% CI 84–99%). Conclusions Low dose amikacin is associated with relatively low rates of aminoglycoside-related adverse events. We hypothesize that low-dose amikacin can be used as a safe and effective treatment for MDR-TB in situations where an adequate regimen cannot be constructed with Group A and B drugs, and where careful monitoring for adverse events is feasible

Granulomatous Pneumocystis Jiroveci Pneumonia Associated with Immune Reconstituted HIV

Pneumocystis jiroveci pneumonia uncommonly presents with pulmonary nodules and granulomatous inflammation. An unusual case of granulomatous P jiroveci pneumonia in an HIV patient with a CD4+ lymphocyte count of greater than 200 cells/mm3, occurring in the context of immune reconstitution with highly active antiretroviral therapy, is described. The case highlights the importance of establishing this diagnosis to institute appropriate therapy.Peer Reviewe

Granulomatous Pneumocystis Jiroveci Pneumonia Associated with Immune Reconstituted HIV

Pneumocystis jiroveci pneumonia uncommonly presents with pulmonary nodules and granulomatous inflammation. An unusual case of granulomatous P jiroveci pneumonia in an HIV patient with a CD4+ lymphocyte count of greater than 200 cells/mm3, occurring in the context of immune reconstitution with highly active antiretroviral therapy, is described. The case highlights the importance of establishing this diagnosis to institute appropriate therapy

South African tobacco smoking cessation clinical practice guideline

Tobacco smoking (i.e. cigarettes, rolled tobacco, pipes, etc.) is associated with significant health risks, reduced life expectancy and negative personal and societal economic impact. Smokers have an increased risk of cancer (i.e. lung, throat, bladder), chronic obstructive pulmonary disease (COPD), tuberculosis and cardiovascular disease (i.e. stroke, heart attack). Smoking affects unborn babies, children and others exposed to second hand smoke. Stopping or 'quitting' is not easy. Nicotine is highly addictive and smoking is frequently associated with social activities (e.g. drinking, eating) or psychological factors (e.g. work pressure, concerns about body weight, anxiety or depressed mood). The benefits of quitting, however, are almost immediate, with a rapid lowering of blood pressure and heart rate, improved taste and smell, and a longer-term reduction in risk of cancer, heart attack and COPD. Successful quitting requires attention to both the factors surrounding why an individual smokes (e.g. stress, depression, habit, etc.) and the symptoms associated with nicotine withdrawal. Many smokers are not ready or willing to quit and require frequent motivational input outlining the benefits that would accrue. In addition to an evaluation of nicotine dependence, co-existent medical or psychiatric conditions and barriers to quitting should be identified. A tailored approach encompassing psychological and social support, in addition to appropriate medication to reduce nicotine withdrawal, is likely to provide the best chance of success. Relapse is not uncommon and reasons for failure should be addressed in a positive manner and further attempts initiated when the individual is ready. Key steps in smoking cessation include: (i) identifying all smokers, alerting them to the harms of smoking and benefits of quitting; (ii) assessing readiness to initiate an attempt to quit; (iii) assessing the physical and psychological dependence to nicotine and smoking; (iv) determining the best combination of counselling/support and pharmacological therapy; (v) setting a quit date and provide suitable resources and support; (vi) frequent follow-up as often as possible via text/telephone or in person; (vii) monitoring for side-effects, relapse and on-going cessation; and (viii) if relapse occurs, providing the necessary support and encourage a further attempt when appropriate