High sensitivity of ultrasound for the diagnosis of tuberculosis in adults in South Africa: A proof-of-concept study.

BACKGROUND: There are limited data on the performance characteristics of ultrasound for the diagnosis of pulmonary tuberculosis in both HIV-positive and HIV-negative persons. The objective of this proof-of-concept study was to determine the sensitivity and specificity of ultrasound for the diagnosis of tuberculosis in adults. METHODS: Comprehensive thoracic and focused abdominal ultrasound examinations were performed by trained radiologists and pulmonologists on adults recruited from a community multimorbidity survey and a primary healthcare clinic in KwaZulu-Natal Province, South Africa. Sputum samples were systematically collected from all participants. Sensitivity and specificity of ultrasound to detect tuberculosis were calculated compared to a reference standard of i) bacteriologically-confirmed tuberculosis, and ii) either bacteriologically-confirmed or radiologic tuberculosis. RESULTS: Among 92 patients (53 [58%] male, mean age 41.9 [standard deviation 13.7] years, 49 [53%] HIV positive), 34 (37%) had bacteriologically-confirmed tuberculosis, 8 (9%) had radiologic tuberculosis with negative bacteriologic studies, and 50 (54%) had no evidence of active tuberculosis. Ultrasound abnormalities on either thoracic or abdominal exams were detected in 31 (91%) participants with bacteriologic tuberculosis and 27 (54%) of those without tuberculosis. Sensitivity and specificity of any ultrasound abnormality for bacteriologically-confirmed tuberculosis were 91% (95% confidence interval [CI] 76%-98%) and 46% (95% CI 32%-61%). Sensitivity and specificity of any ultrasound abnormality for either bacteriologically-confirmed or radiologic tuberculosis were 86% (95% CI 71%-95%) and 46% (95% CI 32%-61%). Overall performance did not appear to differ markedly between participants with and without HIV. CONCLUSION: A comprehensive ultrasound scanning protocol in adults in a high TB burden setting had high sensitivity but low specificity to identify bacteriologically-confirmed tuberculosis.

A Lung Ultrasound Scanning Technique for Children and Adults in Low-Resource Settings: Preliminary Experiences in Sub-Saharan Africa.

Lung ultrasound is increasingly used as a diagnostic tool for pulmonary pathologies by nonspecialist clinicians in resource-limited settings where chest X-ray may not be readily available. However, the optimal technique for lung ultrasound in these settings is not yet clearly defined. We describe here our experience of implementing a standardized, focused six-zone, 12-view lung ultrasound scanning technique with a high-frequency probe in both adults and children in a resource-limited setting in sub-Saharan Africa. Our experience suggests that this may be a feasible technique to rapidly introduce lung ultrasound to new learners that can be adapted to emergency or outbreak settings. However, research is needed to determine how this technique compares with clinical examination and other available tests for the diagnosis of pathology commonly encountered in resource-limited settings.

Sonographic findings in visceral leishmaniasis - A narrative review.

BACKGROUND: Visceral leishmaniasis (VL) is predominantly a neglected tropical parasitic disease but may also be acquired by travellers. We aimed at summarizing knowledge on sonographic presentation of VL to better understand sonographic features of VL. METHODS: PubMed was searched for studies and case reports presenting original data on sonographic findings of VL, published before August 13th, 2019. Demographic, clinical, and sonographic data were extracted and summarized in a qualitative approach. RESULTS: A total of 36 publications were included in this review; 27 of these were case reports and the remainder were prospective or retrospective studies. No study reported systematic cross-sectional comparative imaging. Overall, publications reported on 512 patients with VL of whom 12 were reported HIV-infected. Spleno- and hepatomegaly were the most frequently reported findings. Further relevant and repeatedly reported findings were splenic and hepatic lesions, abdominal lymphadenopathy, pleural and pericardial effusion and ascites. Reported focal splenic lesions were heterogeneous in size, shape, and echogenicity. Several publications reported gradual diminution and resolution of sonographic findings with VL treatment. CONCLUSION: Available literature on sonographic findings of VL is limited. Available reports indicate that spleno- and hepatomegaly, free fluid, abdominal lymphadenopathy, and focal splenic lesions may be common sonographic features in patients with VL. Because of the apparent overlap of sonographic features of VL, extrapulmonary tuberculosis and other conditions, interpretation of sonographic findings needs to be made with particular caution.

Lung Ultrasound Findings Compared with Chest X-Ray Findings in Known Pulmonary Tuberculosis Patients: A Cross-Sectional Study in Lima, Peru.

Lung ultrasound (LUS) is highly portable and has excellent diagnostic accuracy for pneumonia compared with conventional radiography, but the literature on its use in pulmonary tuberculosis (PTB) is limited. This study characterized LUS lesions in patients with PTB and compared them with chest X-ray (CXR) findings. Adult patients in Lima, Peru, with PTB were recruited within 1 week of starting antituberculosis treatment. Comprehensive LUS was performed in all patients at enrollment and assessed for consolidation, small subpleural consolidation (SPC, hypothesized to be a marker of CXR consolidation), cavity, pleural effusion, pathologic B-lines, and miliary pattern. Patient CXRs were digitized and interpreted by a board-certified radiologist. Fifty-one patients were included in the final analysis. Lung ultrasound detected either consolidation or SPC in 96.1% of participants. No significant difference was found between the LUS detection of a composite of consolidation or SPC, and CXR detection of consolidation (96.1% versus 98%, P > 0.99). The proportion of patients with cavity detected by LUS was significantly lower than that detected by CXR (5.9% versus 51%, P < 0.001). Overall, LUS detection of consolidation or SPC may be a sensitive marker for diagnosis of PTB. Lung ultrasound demonstrated poor ability to detect radiographically identified cavity, although previous studies suggest SPC could add specificity for the diagnosis of PTB. Based on its portability and evidence base for diagnosing other pulmonary diseases, LUS may have a role in screening and diagnosis of PTB in areas without ready access to CXR. Further studies should evaluate its diagnostic accuracy in patients with and without PTB.

Point-of-Care Ultrasound in Resource-Limited Settings: Common Applications.

Point-of-care ultrasound (POCUS) is used increasingly in resource-limited settings (RLSs), particularly as inexpensive ultrasound machines and evidence-based protocols become more available. POCUS often is the only imaging modality available in such settings, and it has the potential to significantly affect patient care. This article discusses four case-based reviews of POCUS in RLSs for several common diseases: pediatric pneumonia; extrapulmonary tuberculosis; ectopic pregnancy; and tropical parasitic diseases, including echinococcus, schistosomiasis, and amebiasis. It concludes with a discussion of the logistical considerations specific to implementing POCUS in RLSs, particularly equipment and training. The literature reviewed suggests that POCUS has the potential to improve the diagnosis and management of multiple conditions in RLSs, although further research is needed.