Defining 'Satisfactory Response' to Therapy in Abdominal Tuberculosis: A Work in Progress

Serial measurements of faecal calprotectin may discriminate intestinal tuberculosis and Crohn's disease in patients started on antitubercular therapy

BACKGROUND

Response to antitubercular therapy (ATT) is often used to differentiate intestinal tuberculosis (ITB) from Crohn's disease. Role of non-invasive biomarkers to predict mucosal response to ATT is unclear.

MATERIALS AND METHODS

A prospective study to compare faecal calprotectin and serum C-reactive protein (CRP) levels at diagnosis, 2 and 6 months of ATT in patients with suspected ITB started on ATT was done. The patients were eventually divided into two groups: ITB or alternative diagnosis (OTH). Decline of calprotectin and CRP levels was used to compute area under the receiver operating characteristic (AUROC) to predict mucosal healing at 2 months.

RESULTS

Thirty-seven patients (mean age: 34.95 ± 16.35 years, 23 males) were included and 28 (75.67%) were diagnosed as ITB while nine (24.32%) had alternative diagnosis (OTH). The median faecal calprotectin values of ITB and OTH groups at baseline, 2 months and 6 months were 216 and 282 µg/g (P = 0.466), 43 and 216 µg/g (P = 0.003), and 26 and 213 µg/g (P < 0.001), respectively. The median CRP values at baseline, 2 months and 6 months were 18 and 30 mg/L (P = 0.767), 4.7 and 15 mg/L (P = 0.025), and 3 and 10.85 mg/L (P = 0.068), respectively. The AUROC of percent decline in faecal calprotectin and serum CRP at 2 months for mucosal healing were 0.8287 [95% confidence inteval (CI) 0.6472-1] and 0.6018 (95% CI 0.4079-0.7957), respectively.

CONCLUSION

Faecal calprotectin can help in assessing response to therapy in suspected ITB patients started on empirical ATT.

Imaging in discriminating intestinal tuberculosis and Crohn's disease: past, present and the future

Introduction: Intestinal tuberculosis (ITB) and Crohn's disease (CD) have similar clinical presentation, but require different treatment approaches. Despite advances in various endoscopic, imaging, microbiological, and histological techniques, the differentiation of these two entities is often difficult. Newer radiological and image acquisition modalities have now become indispensable tools for evaluation of these two diseases.Areas covered: This review summarizes the currently available literature on various radiological investigations to differentiate ITB from CD. This review also enumerates the newer modalities in image acquisition techniques and their potential role for differentiating these two diseases. At present abdominal computed tomography (CT) scan is used as a first line investigation for differentiating ITB from CD. Magnetic resonance imaging (MRI) is preferred in pediatric patients and for follow-up studies.Expert opinion: Role of newer modalities like contrast enhanced abdominal ultrasound, perfusion CT, advanced MRI and positron emission tomography (PET) is evolving and requires further exploration. Till further robust studies are available, differentiation between ITB and CD requires use of a combination of clinical, endoscopic, serological, histological, and radiological parameters rather than relying on a single test.

Evaluation of treatment response in extrapulmonary tuberculosis in a low-resource setting

Background

Diagnosing extrapulmonary tuberculosis (EPTB) is challenging and many patients are initiated on empirical anti-TB treatment without a laboratory confirmed diagnosis. Monitoring treatment response is thus important to ensure correct diagnosis and proper disease management. The definition of satisfactory response to treatment in EPTB remains unclear. The objectives of this study were to describe the clinical presentation of EPTB and the effect of treatment on clinical parameters. Further, to assess if simple clinical parameters, without laboratory data, could evaluate treatment response.

Methods

Prospective cohort study of presumptive EPTB patients at Mnazi Mmoja Hospital, Zanzibar. By using a composite reference standard, patients were categorized as TB or non-TB cases. The TB patients were followed during anti-TB treatment.

Results

There were 64 TB and 62 non-TB cases. The frequency of symptoms at baseline were comparable in TB and non-TB patients, with lymphadenitis and pleuritis as the most common manifestations. Among TB cases, there was a trend towards regression of lymphadenopathy after 2 months, and at treatment completion 24/28 (86%) cases showed full regression. Weight gain ≥5% was reported in 36/49 (73%) of the TB patients at 2 months and in 38/46 (83%) at treatment completion. After 2 months of treatment, a combination of clinical parameters; improvement of symptoms (50/50), ≥5% weight gain (36/49) and regression of physical signs (45/49) correlated with the treatment response.

Conclusions

An algorithm including only simple clinical parameters could be used as an easy tool to assess treatment responses in low-resource settings. However, this needs to be tested on a larger sample size.