Is the Initial Size of Tuberculous Lymphadenopathy associated with Lymph Node Enlargement during Treatment?

Clinical Course of Patients With Mediastinal Lymph Node Tuberculosis and Risk Factors for Paradoxical Responses

BACKGROUND

Paradoxical responses (PR) occur more frequently in lymph node tuberculosis (LNTB) than in pulmonary tuberculosis and present difficulties in differential diagnosis of drug resistance, new infection, poor patient compliance, and adverse drug reactions. Although diagnosis of mediastinal LNTB has become much easier with the development of endosonography, limited information is available. The aim of this study was to investigate the clinical course of mediastinal LNTB and the risk factors associated with PR.

METHODS

Patients diagnosed with mediastinal LNTB via endosonography were evaluated retrospectively between October 2009 and December 2019. Multivariable logistic regression was applied to evaluate the risk factors associated with PR.

RESULTS

Of 9,052 patients who underwent endosonography during the study period, 158 were diagnosed with mediastinal LNTB. Of these, 55 (35%) and 41 (26%) concurrently had pulmonary tuberculosis and extrapulmonary tuberculosis other than mediastinal LNTB, respectively. Of 125 patients who completed anti-tuberculosis treatment, 21 (17%) developed PR at a median of 4.4 months after initiation of anti-tuberculosis treatment. The median duration of anti-tuberculosis treatment was 6.3 and 10.4 months in patients without and with PR, respectively. Development of PR was independently associated with age < 55 years (adjusted odds ratio [aOR], 5.72; 95% confidence interval [CI], 1.81-18.14; P = 0.003), lymphocyte count < 800/μL (aOR, 8.59; 95% CI, 1.60-46.20; P = 0.012), and short axis diameter of the largest lymph node (LN) ≥ 16 mm (aOR, 5.22; 95% CI, 1.70-16.00; P = 0.004) at the time of diagnosis of mediastinal LNTB.

CONCLUSION

As PR occurred in one of six patients with mediastinal LNTB during anti-tuberculosis treatment, physicians should pay attention to patients with risk factors (younger age, lymphocytopenia, and larger LN) at the time of diagnosis.

[Parardoxical reaction following tuberculosis treatment in non HIV-infected patients]

A paradoxical reaction is the worsening of prior existing, or the appearance of, new tuberculous lesions, following the initiation of treatment with anti-tuberculous drugs, after the exclusion of poor compliance, malabsorption, drug interaction or multiresistant mycobacteria. Well known and well managed in the context of HIV coinfection, it is not well known outside this context. An increasing number of publications have described this syndrome. This review aims to describe the pathogenic, epidemiological, clinical, prognostic and therapeutic elements of non-HIV-associated paradoxical reactions. It involves a reversal of the Mycobacterium tuberculosis-induced immunodepression along with a heightened detrimental pro-inflammatory profile caused by efficient drug treatment. Extra-thoracic locations, especially lymph nodes and neurological, malnutrition and initial lymphopenia are the principal risk factors. The median delay is 40±20 days after the onset of treatment. Corticosteroids are the mainstay of the management. Anti-TNF-α drugs show good results in corticosteroid refractory cases. The prognosis is good overall except in neurological forms. The place of preventive methods remains to be established.