Predictors of pulmonary involvement in patients with extra-pulmonary tuberculosis

The prevalence, risk factors, and public health consequences of peripheral lymph node-associated clinical and subclinical pulmonary tuberculosis

OBJECTIVES

Relatively little is known about the prevalence, risk factors, and public health consequences of peripheral lymph node (PLN)-associated pulmonary tuberculosis (PTB).

METHODS

We developed a 10-year (2010-2019) population-based cohort of PLNTB patients in Canada. We used systematically collected primary source data and expert reader chest radiograph interpretations in a multivariable logistic regression to determine associations between sputum culture positivity and demographic, clinical, and radiographic features. Public health risks were estimated among contacts of PLNTB patients.

RESULTS

There were 306 patients with PLNTB, among whom 283 (92.5%) were 15-64 years of age, 159 (52.0%) were female, and 293 (95.8%) were foreign-born. Respiratory symptoms were present in 21.6%, and abnormal chest radiograph in 23.2%. Sputum culture positivity ranged from 12.9% in patients with no symptoms and normal lung parenchyma to 66.7% in patients with both. Respiratory symptoms, abnormal lung parenchyma, and HIV-coinfection (borderline) were independent predictors of sputum culture positivity (odds ratio [OR] 2.24 [95% confidence interval [CI] 1.15-4.39], P = 0.01, OR 4.78 [95% CI 2.41-9.48], P < 0.001, and OR 2.54 [95% CI 0.99-6.52], P = 0.05), respectively. Among contacts of sputum culture-positive PLNTB patients, one secondary case and 16 new infections were identified.

CONCLUSION

Isochronous PTB is common in PLNTB patients. Routine screening of PLNTB patients for PTB is strongly recommended.

A Cross-sectional Study of Patients With Extrapulmonary Tuberculosis and Normal Chest Radiographs - What Characteristics Were Associated With Sputum Culture Positivity?

BACKGROUND

Recognizing pulmonary involvement in tuberculosis (TB) patients is necessary to prevent TB transmission. We describe frequency and characteristics of patients with extrapulmonary TB (EPTB), normal chest radiographs, and positive sputum culture.

METHODS

We analyzed data of patients ≥15 years of age with EPTB reported to the California TB registry during 2011-2017 with cultured sputum and normal chest radiographs using generalized linear modeling to estimate prevalence ratios associated with positive sputum culture. Demographic, behavioral, clinical characteristics, and testing were compared for patients with positive and negative sputum culture.

RESULTS

Of 1635 patients with EPTB and normal chest radiographs, 937 (57%) had sputum culture performed, and 127 (13%) patients had positive results for Mycobacterium tuberculosis complex. Patients with positive results were more likely to: be male, experience homelessness, use substances, have HIV, and have >1 disease site. Among 85 patients with HIV co-infection, 54% had positive culture results compared with 9.5% among 852 patients without HIV co-infection. Patients with EPTB in more than 1 site were also more likely to have a positive sputum culture.

CONCLUSIONS

Culturing sputum from patients with EPTB identified pulmonary cases not detected by chest radiograph, particularly among patients with HIV or >1 disease site.

Concomitant pulmonary disease is common among patients with extrapulmonary TB

BACKGROUND :

Microbiologic screening of extrapulmonary TB (EPTB) patients could inform recommendations for aerosol precautions and close contact prophylaxis. However, this is currently not routinely recommended in India. Therefore, we estimated the proportion of Indian patients with EPTB with microbiologic evidence of pulmonary TB (PTB).

METHODS :

We characterized baseline clinical, radiological and sputum microbiologic data of 885 adult and pediatric TB patients in Chennai and Pune, India, between March 2014 and November 2018.

RESULTS :

Of 277 patients with EPTB, enhanced screening led to the identification of 124 (45%) with concomitant PTB, including 53 (19%) who reported a cough >2 weeks; 158 (63%) had an abnormal CXR and 51 (19%) had a positive sputum for TB. Of 70 participants with a normal CXR and without any cough, 14 (20%) had a positive sputum for TB. Overall, the incremental yield of enhanced screening of patients with EPTB to identify concomitant PTB disease was 14% (95% CI 12–16).

CONCLUSIONS :

A high proportion of patients classified as EPTB in India have concomitant PTB. Our results support the need for improved symptom and CXR screening, and recommends routine sputum TB microbiology screening of all Indian patients with EPTB.

Plasma interferon-γ-inducible protein 10 (IP-10) levels correlate with disease severity and paradoxical reactions in extrapulmonary tuberculosis

BACKGROUND

With 1.5 million deaths worldwide in 2018, tuberculosis (TB) remains a major global public health problem. While pulmonary TB (PTB) is the most common manifestation, the proportion of extrapulmonary TB (EPTB) is increasing in low-burden countries. EPTB is a heterogeneous disease entity posing diagnostic and management challenges due to the lack of reliable biomarkers. In this study, we prospectively evaluated clinical data and treatment response which were correlated with different biomarkers.

METHODS

The study was conducted at the University Hospital of Cologne. 20 patients with EPTB were enrolled. We analyzed plasma interferon-γ-inducible protein 10 (IP-10) levels in plasma by ELISA for up to 12 months of treatment. In addition, the QuantiFERON^®-TB Gold Plus (QFT^® Plus) test was performed during the course of treatment. Clinical data were assessed prospectively and correlated with QFT^® Plus and IP-10 levels.

RESULTS

Plasma IP-10 levels were found to be significantly increased (p < 0.001) in patients with extensive disease compared to patients with limited disease (cervical lymph node TB) or healthy controls. In patients with clinically confirmed paradoxical reaction (PR), a further increase of IP-10 was noted. IFN-γ measured by the QFT^® Plus test did not decrease significantly during the course of treatment. Of note, in four EPTB patients (20%) without radiographic pulmonary involvement, sputum culture was positive for Mycobacterium tuberculosis.

CONCLUSION

Our data demonstrate that IP-10 may be a valuable biomarker for estimation of disease severity in EPTB and monitoring of the disease course in extensive forms. However, IP-10 may be less suitable for diagnosis and monitoring of EPTB patients with limited disease. The QFT^® Plus test does not appear to be a suitable marker for therapy monitoring. Sputum should be examined in EPTB patients even in case of normal diagnostic imaging of the chest.

Description of demographic and clinical characteristics of extrapulmonary tuberculosis in Shandong, China

BACKGROUND

According to the clinical manifestation, tuberculosis (TB) is divided into pulmonary tuberculosis (PTB) and extrapulmonary tuberculosis (EPTB). The incidence rate of EPTB has increased in many countries. The demographic and clinical characteristics of EPTB in China remain still unclear.

MATERIALS AND METHODS

We retrospectively analyzed the medical records of 5,624 hospitalized patients with positive M. tuberculosis culture between January 2008 and June 2013 in Shandong province. We investigated the epidemiological, demographic, and clinical characteristics of patients with EPTB.

RESULTS

Among 5,624 hospitalized TB patients with positive M. tuberculosis culture, 4,277 (76.05 %) had PTB, 618 (10.99 %) had EPTB, and 729 (12.96 %) had both PTB and EPTB. The proportion of EPTB increased significantly from 6.97 % in 2008 to 19.98 % in 2012 (p <0.001).  The most frequent sites or foci of EPTB were pleura (63.27 %), followed by bone/joint (13.75 %), and lymph nodes (8.9 %). The mean duration of treatment for pleural TB was eight months and for EPTB in the other foci was more than 15 months.

CONCLUSION

The proportion of EPTB in Shandong province has significantly increased. Clinicians need to be aware of the trend and remain vigilant against EPTB. EPTB requires prolonged treatment, and clinical supervision should be strengthened to prevent drug resistance. HIPPOKRATIA 2020, 24(1): 27-32.

Population dynamics and tuberculosis: a cross sectional study of an overlooked disease in Saudi Arabia

BACKGROUND

International travel, migration and human population movements facilitate the spread of tuberculosis (TB).

OBJECTIVE

To study the impact of poorly screened expatriates working in Saudi Arabia on the local incidence of TBs.

PATIENTS AND METHODS

This cross sectional study was carried out in the Chest Disease Hospital, Taif. All confirmed cases of TB from June 2009 to May 2010 admitted to the hospital were enrolled. Inclusion criteria were diagnosed cases of TB (pulmonary & extra-pulmonary) in patients between the ages of 14 to 65 years. Patients with HIV and coexistent malignancies were excluded. The age, gender and ethnic group of each patient was recorded, and patients were divided into two groups. Of the two groups, Group A consisted of Taif residents and group B of patients referred from other cities in the country.

RESULTS

Of the 686 cases studied, 370 (54%) were Saudi nationals (Group A = 80 & Group B = 290) and 316 (46%) cases were from other countries. Males outnumbered females and most of the patients were aged 20 to 29 years. The number of cases from the areas close to the pilgrimage sites, i.e. Makah (233) and Jeddah (275), outnumbered those in Taif (110).

CONCLUSIONS

Our study identifies an increased prevalence of TB cases in areas close to the pilgrimage (Group B). The higher proportion of non-Saudi TB patients in group B is most likely explained by the higher number of poorly screened illegal expatriates in the region.

Determination of Sites Involved, HIV Co-Infection & Utility of Diagnostic Modalities in EPTB

BACKGROUND

Tuberculosis remains a major global public health problem and an on-going epidemic. Though the chief objectives of the Revised National Tuberculosis Control Programme (RNTCP) in detecting and curing the infectious pulmonary cases is well taken, there has been a steady rise in the number of Extra Pulmonary Tuberculosis (EPTB) cases as documented in several studies. EPTB which usually constitutes around 15%-20% of the total TB cases is now being increasingly reported due to a combination of better diagnostic facilities, and the HIV pandemic. Though several studies have shown increasing prevalence of EPTB, only few studies are available, especially in the Indian scenario, that study the pattern and risk factors. Hence, this retrospective observational study was undertaken to determine the sites of the involvement, HIV co-infection and usefulness of various diagnostic modalities in EPTB affecting patients attending a medical college DOTS clinic.

MATERIAL AND METHODS

One hundred ten EPTB patients referred to the DOTS clinics of the TB & Chest department from the period Dec 2010- Mar 2012 were included in the study. The diagnosis of EPTB was established by combined clinical, microbiological, histopathological &/or imaging modalities. Their medical records were assessed to determine the age distribution, gender and anatomical sites of involvement. The presence of co-morbid conditions like smoking history, alcoholism, diabetic and HIV status were noted. BCG status and Mantoux test readings were recorded. The different diagnostic tests used in confirming EPTB at different sites were recorded. Chest x-ray was analysed for all patients to assess coexisting pulmonary involvement. All patients were followed to assess the outcome of treatment.

RESULTS

The mean age of patients was 34.4. The male to female ratio was 58:52 showing a slight male predominance. The most common site of involvement was lymph node followed by pleural effusion and abdominal TB. The prevalence of lymph node TB was noted to be higher in female patients as compared to other sites of EPTB. Mantoux test was positive in 57 (51.8%) patients. HIV co-infection was noted in only 3 (2.7%) patients. Concomitant pulmonary involvement was seen in 19 (17.3%) patients.

CONCLUSIONS

Lymph node was the most common site involvement showing a significant female preponderance followed by pleural effusion and abdominal TB. The rates of HIV co-infection and diabetes mellitus were 2.7% and 20% respectively. The most useful diagnostic modality was tissue sampling followed by imaging. Mantoux test is not unequivocal for the diagnosis of EPTB.