TB or not TB: A comprehensive review of imaging manifestations of abdominal tuberculosis and its mimics

Acute abdomen revealing abdominal tuberculosis complicated by a proximal jejunal perforation: Case report

Abdominal tuberculosis (TB) remains a significant health concern globally, particularly in regions with high endemicity such as North Africa and Morocco. Despite advances in diagnostic modalities, the nonspecific presentation of abdominal TB poses challenges for timely diagnosis and management. Here, we report a case of abdominal TB in a critically state of a young man from Morocco, presenting with acute abdominal pain and signs of sepsis. Radiological investigations revealed features suggestive of intestinal perforation complicating peritoneal TB. Urgent laparotomy confirmed the diagnosis, yet the patient succumbed to advanced sepsis postoperatively. This case underscores the complexity of abdominal TB diagnosis and management, necessitating a high index of suspicion and multidisciplinary collaboration. With evolving surgical techniques and ongoing research efforts, optimizing strategies for early detection and treatment of abdominal TB remains imperative, particularly in endemic regions.

Extrahepatic biliary tract tuberculosis: A case report and literature review

INTRODUCTION

Tuberculosis is a chronic infectious disease that often has a latent period after the initial infection. Tuberculosis most often affects the lungs but it can also affect other parts of the body. Vietnam is in pandemic area of tuberculosis.

CASE REPORT

We present a rare case of a 42-year-old male patient admitted to the hospital with a history of progressive jaundice. Magnetic resonance imaging (MRI) revealed a 26 × 33 mm tuberculous mass located at the intersection between the cystic duct and the common hepatic duct, leading to dilation of the intrahepatic biliary ducts on both sides. Initially diagnosed with a Klatskin type II tumor, the patient underwent surgery to remove the mass and create a biliary-enteric anastomosis. However, the pathological report of the postoperative specimens concluded a diagnosis of necrotizing granulomatous inflammation caused by tuberculosis.

CASE DISCUSSION

Obstructive jaundice secondary to tuberculosis is a rare condition that can be caused due to the tuberculous enlargement of the pancreatic head, tuberculous lymphadenitis, tuberculous biliary strictures, or a tuberculous retroperitoneal mass. Extrapulmonary tuberculosis usually results from hematogenous dissemination or contiguous spread from adjacent organs. Symptoms vary depending on the affected organ but typically include fever, fatigue, and weight loss. Hepatobiliary tuberculosis is usually secondary to pulmonary or gastrointestinal tuberculosis.

CONCLUSION

Hepatobiliary tuberculosis is a rare disease that affects the liver and bile duct system. It is difficult to diagnose because it does not have any specific symptoms and can be easily misdiagnosed with other diseases.

Revisiting the Era of Intestinal Tuberculosis: A Case Presenting As Small Bowel Obstruction With Classical Imaging and Histopathological Appearances

The incidence of tuberculosis (TB) worldwide is still significantly high, with India contributing a high global TB burden. This case study features a 49-year-old male who had complaints of pain and abdominal distention for one and a half months. An erect abdominal radiograph showed features suggesting small bowel obstruction. Contrast-enhanced computed tomography (CT) of the abdomen was done. It showed multiple strictures involving the distal jejunum and ileum, causing small bowel obstruction. There was mesenteric and retroperitoneal lymphadenopathy with central necrosis and ascites. The patient was operated on for a small bowel obstruction. The resected intestine showed four strictures, tiny nodules on the serosal surface, and many enlarged lymph nodes. Representative tissue from these areas showed the typical picture of multiple caseating granulomas and fibrosis. Ziehl-Neelsen (ZN) staining highlighted the acid-fast bacilli (AFB). The suspicion index for intestinal tuberculosis (ITB) should be kept high while evaluating patients with intestinal obstruction presenting in endemic areas and high-risk populations, such as HIV-infected, undernourished, immunocompromised, and those with diabetes, smoking, and alcohol addiction.

A rare case of tuberculous abscess on the anterior abdominal wall

Intramuscular tuberculosis (TB) is a rare manifestation of extrapulmonary TB because of the lower rate of survival and multiplication of Mycobacterium tuberculosis in striated muscle. A 27-year-old woman with no previous history of tuberculosis presented with painless, progressive swelling of the anterior lower abdomen. Abdominal ultrasonography and computed tomography (CT) scan revealed a well-defined, enhancing thick wall cystic mass in the lower rectus abdominis muscle extending to pectineus muscle. Open drainage and wide debridement were performed before prescribing antituberculosis drugs.

Imaging recommendations and algorithms for pediatric tuberculosis: part 2-extrathoracic tuberculosis

Despite advances in diagnosis and treatment in recent years, tuberculosis (TB) remains a global health concern. Children are amongst the most vulnerable groups affected by this disease. Although TB primarily involves the lungs and mediastinal lymph nodes, it can affect virtually any organ system of the body. Along with clinical history combined with physical examination and laboratory tests, various medical imaging tools help establish the diagnosis. Medical imaging tests are also helpful for follow-up during therapy, to assess complications and exclude other underlying pathologies. This article aims to discuss the utility, strengths and limitations of medical imaging tools in the evaluation of suspected extrathoracic TB in the pediatric population. Imaging recommendations for the diagnosis will be presented along with practical and evidence-based imaging algorithms to serve as a guide for both radiologists and clinicians.

Hepatic Manifestations of Systemic Diseases

In addition to being the primary target of infections such as viral hepatitis, the liver may also be affected by systemic disease. These include bacterial, mycotic, and viral infections, as well as autoimmune and infiltrative diseases. These conditions generally manifest as abnormal liver biochemistries, often with a cholestatic profile, and may present with additional signs/symptoms such as jaundice and fever. A high index of suspicion and familiarity with potential causal entities is necessary to guide appropriate testing, diagnosis, and treatment.

Abdominal Tuberculosis Presenting With Small Bowel Obstruction: A Case Report

Abdominal tuberculosis (TB) is a common form of extrapulmonary TB (EXPTB). It is being reported increasingly, especially in high-burden regions of the world. We present a case of a 37-year-old male who presented to the emergency department with clinical features suggestive of bowel obstruction. On clinical examination, the patient exhibited generalized tenderness in the abdomen. A subsequent CT scan revealed features consistent with small bowel obstruction. The patient underwent a diagnostic laparoscopy, which was converted to an exploratory laparotomy due to intraoperative findings of adhesions. Notably, there were extensive peritoneal deposits and adhesions between bowel loops. Peritoneal biopsies were obtained and subjected to the acid-fast bacillus (AFB) smear and culture, which demonstrated the growth of the Mycobacterium tuberculosis complex. As a result, the patient was initiated on antituberculous therapy.

Differentiating peritoneal tuberculosis and peritoneal carcinomatosis based on a machine learning model with CT: a multicentre study

PURPOSE

It is still a challenge to make early differentiation of peritoneal tuberculosis (PTB) and peritoneal carcinomatosis (PC) clinically as well as on imaging and laboratory tests. We aimed to develop a model to differentiate PTB from PC based on clinical characteristics and primary CT signs.

METHODS

This retrospective study included 88 PTB patients and 90 PC patients (training cohort: 68 PTB patients and 69 PC patients from Beijing Chest Hospital; testing cohort: 20 PTB patients and 21 PC patients from Beijing Shijitan Hospital). The images were analyzed for omental thickening, peritoneal thickening and enhancement, small bowel mesentery thickening, the volume and density of ascites, and enlarged lymph nodes (LN). Meaningful clinical characteristics and primary CT signs comprised the model. ROC curve was used to validate the capability of the model in the training and testing cohorts.

RESULTS

There were significant differences in the following aspects between the two groups: (1) age; (2) fever; (3) night sweat; (4) cake-like thickening of the omentum and omental rim (OR) sign; (5) irregular thickening of the peritoneum, peritoneal nodules, and scalloping sign; (6) large ascites; and (7) calcified and ring enhancement of LN. The AUC and F1 score of the model were 0.971 and 0.923 in the training cohort and 0.914 and 0.867 in the testing cohort.

CONCLUSION

The model has the potential to distinguish PTB from PC and thus has the potential to be a diagnostic tool.

Diagnosis of abdominal tuberculosis by multi-targeted (mpt64 and IS6110) loop-mediated isothermal amplification assay

BACKGROUND AND AIM

Diagnosis of abdominal TB is an exigent task due to variable anatomical sites and non-specific clinical manifestations that closely resemble other diseases. Most of the available diagnostic modalities yield low sensitivities and need expertise to handle the specialized equipment. Hence, there is an urgent need to develop a rapid and reliable diagnostic test, so as to reduce the unnecessary morbidity. Therefore, we designed a multi-targeted loop-mediated isothermal amplification (MT-LAMP) for diagnosing abdominal TB.

METHODS

We evaluated an MT-LAMP (using mpt64 and IS6110) to diagnose abdominal TB within ascitic fluids and intestinal/peritoneal biopsies and compared these results with multiplex-PCR (M-PCR) using the same targets. MT-LAMP products were analyzed by gel electrophoresis and visual detection methods, that is, hydroxy naphthol blue and SYBR Green I reaction.

RESULTS

Sensitivities of 80.9% and 84.6% were obtained in suspected (n = 42) and total abdominal TB (n = 52) cases, respectively by gel-based MT-LAMP, with 97.3% (n = 37) specificity in non-TB controls. Notably, sensitivities attained by gel-based/SYBR Green I MT-LAMP in both clinically suspected and total abdominal TB cases were significantly higher (P < 0.05) than M-PCR. Furthermore, sensitivity obtained with SYBR Green I was equivalent to that of gel-based MT-LAMP, while somewhat lesser specificity (94.6%) was attained with SYBR Green I, compared with gel-based MT-LAMP.

CONCLUSION

Both gel-based and SYBR Green MT-LAMP exhibited equivalent sensitivities to diagnose abdominal TB. Because SYBR Green LAMP is easier to perform than a gel-based assay, we are currently focused on improving the specificity of this assay so as to develop a diagnostic kit.

PET/CT features of a novel gallium-68 labelled hypoxia seeking agent in patients diagnosed with tuberculosis: a proof-of-concept study

INTRODUCTION

Positron emission tomography/computed tomography (PET/CT) in infection and inflammation has yielded promising results across a range of radiopharmaceuticals. In particular, PET/CT imaging of tuberculosis (TB) allows for a better understanding of this complex disease by providing insights into molecular processes within the TB microenvironment. TB lesions are hypoxic with research primarily focussed on cellular processes occurring under hypoxic stress. With the development of hypoxia seeking PET/CT radiopharmaceuticals, that can be labelled in-house using a germanium-68/gallium-68 (68Ge/68Ga) generator, a proof-of-concept for imaging hypoxia in TB is presented.

METHODS

Ten patients diagnosed with TB underwent whole-body PET/CT imaging, 60-90 min after intravenous administration of 74-185 MBq (2-5 mCi) 68Ga-nitroimidazole. No oral or intravenous contrast was administered. Images were visually and semiquantitatively assessed for abnormal 68Ga-uptake in the lungs.

RESULTS

A total of 28 lesions demonstrating hypoxic uptake were identified. Low- to moderate-uptake was seen in nodules, areas of consolidation and cavitation as well as effusions. The mean standard uptake value (SUVmean) of the lesions was 0.47 (IQR, 0.32-0.82) and SUVmax was 0.71 (IQR, 0.41-1.11). The lesion to muscle ratio (median, 1.70; IQR, 1.15-2.31) was higher than both the left ventricular and the aorta lesion to blood ratios.

CONCLUSION

Moving towards the development of unique host-directed therapies (HDT), modulation of oxygen levels may improve therapeutic outcome by reprogramming TB lesions to overcome hypoxia. This proof-of-concept study suggests that hypoxia in TB lesions can be imaged and quantified using 68Ga-nitroimidazole PET/CT. Subsequently, hypoxic load can be estimated to inform personalised treatment plans of patients diagnosed with TB.

Mimics of Crohn's Disease

Crohn's disease is a chronic inflammatory disease that can affect any portion of the gastrointestinal tract. Associated symptoms can vary based on the severity of disease, extent of involvement, presence of extraintestinal manifestations, and development of complications. Diagnosis is based on a constellation of findings. Many diseases can mimic Crohn's disease and lead to diagnostic conundrums. These include entities associated with the gastrointestinal luminal tract, vascular disease, autoimmune processes, various infections, malignancies and complications, drug- or treatment-induced conditions, and genetic diseases. Careful consideration of possible causes is necessary to establish the correct diagnosis.

Data Mining for ICD-10 Admission Diagnoses Preceding Tuberculosis within 1 Year among Non-HIV and Non-Diabetes Patients

Delayed diagnosis of tuberculosis (TB) increases mortality and extends the duration of disease transmission. This study aimed to identify significant ICD-10 admission diagnoses preceding TB. All hospital electronic medical records from fiscal year 2015 to 2020 in the Songkhla Province, Thailand were retrieved. After excluding diabetes and HIV patients, a case-control analysis was performed. Exposures of interest were ICD-10 diagnoses on admissions 1–12 months prior to the visit during which TB was detected. Incident cases of respiratory tuberculosis (A15.0–A16.9) that had been admitted with at least one such exposure were chosen. For every case, controls were retrieved from weekly concurrent OPD patients who had the same 10-year interval of age, sex, and preceding admission and discharge week as the case. The 10 most common comorbidities during hospitalization preceding TB with their relative odds ratios (RORs) and 95% confidence intervals were identified. These included five significant exposures related to lower respiratory infection without adequate TB investigation. Significant RORs ranged from 3.10 (unspecified pneumonia) to 34.69 (hemoptysis). Full TB investigation was not performed due to problems with health insurance. In conclusion, the physicians should be informed about this pitfall, and the insurance system should be revised accordingly.

Extrapulmonary tuberculosıs: an old but resurgent problem

Tuberculosis (TB) primarily affects the lungs, but some of its most devastating clinical consequences arise because of its ability to spread from the lungs to other organs. Extrapulmonary TB (EPTB) constitutes 15–20% of all TB cases. Imaging findings are not always specific and can mimic many diseases; therefore, EPTB should be considered in the differential diagnosis, particularly in patients with immune system disorders (AIDS, patients receiving chemotherapy, etc.) and those in other high-risk groups including people with diabetes. The bacterium's passage to the regional lymph nodes is essential for developing a protective T-cell-mediated immune response, but the bacterium can spread hematologically and via the lymphatic system, leading to extrapulmonary involvement. Diagnosis of EPTB in high-risk patients is made based on suspected clinical and radiological findings, but further positive culture and histopathological confirmation may be required in some instances. Radiological evaluations are critical for diagnosis and crucial in planning the treatment and follow-up. This paper aims to review the typical and atypical imaging features and the differential diagnosis of EPTB.

The Diagnostic Deceiver: Radiological Pictorial Review of Tuberculosis

Tuberculosis (TB) is a bacterial infection with Mycobacterium tuberculosis; it is a public health problem worldwide and one of the leading causes of mortality. Since December 2019, the COVID-19 pandemic has created unprecedented health challenges and disrupted the TB health services, especially in high-burden countries with ever-increasing prevalence. Extrapulmonary and even pulmonary TB are an important cause of nonspecific clinical and radiological manifestations and can masquerade as any benign or malignant medical case, thus causing disastrous conditions and diagnostic dilemmas. Clinical manifestations and routine laboratory tests have limitations in directing physicians to diagnose TB. Medical-imaging examinations play an essential role in detecting tissue abnormalities and early suspecting diagnosis of TB in different organs. Radiologists and physicians should be familiar with and aware of the radiological manifestations of TB to contribute to the early suspicion and diagnosis of TB. The purpose of this article is to illustrate the common radiologic patterns of pulmonary and extrapulmonary TB. This article will be beneficial for radiologists, medical students, chest physicians, and infectious-disease doctors who are interested in the diagnosis of TB.

Recent updates in diagnosis of abdominal tuberculosis with emphasis on nucleic acid amplification tests

INTRODUCTION

Abdominal tuberculosis (TB) is a common epitome of extrapulmonary TB (EPTB), wherein peritoneal and intestinal TB are the most prevalent forms. Diagnosis of abdominal TB is a daunting challenge owing to variable anatomical locations, paucibacillary nature of specimens and atypical clinical presentations that mimic other abdominal diseases, such as Crohn's disease and malignancies. In this review, we made a comprehensive study on the diagnosis of abdominal TB.

AREA COVERED

Various modalities employed for abdominal TB diagnosis include clinical features, imaging, bacteriological tests (smear/culture), histopathological/cytological observations, interferon-gamma release assays and nucleic acid amplification tests (NAATs). Among NAATs, loop-mediated isothermal amplification assay, PCR, multiplex-PCR, nested PCR, real-time PCR and GeneXpert® MTB/RIF were discussed. Identification of circulating Mycobacterium tuberculosis cell-free DNA by real-time PCR within ascitic fluids is another useful approach.

EXPERT OPINION

Several novel molecular/immunological methods, such as GeneXpert Ultra, aptamer-linked immobilized sorbent assay, immuno-PCR (I-PCR) and nanoparticle-based I-PCR have recently been developed for detecting pulmonary TB and several EPTB types, which may also be explored for abdominal TB diagnosis. Precise and prompt diagnosis of abdominal TB may initiate an early therapy so as to reduce the complications, i.e. abdominal pain, ascites, abdominal distension, intestinal obstruction/perforation, etc., and avoid surgical involvement.Plain Language SummaryAbdominal tuberculosis (TB) is a manifestation of extrapulmonary TB (EPTB), where peritoneal and intestinal TB are two major forms. Diagnosis of abdominal TB is difficult owing to low bacterial load present in clinical samples and non-specific clinical presentations as it mimics other diseases such as inflammatory bowel diseases, abdominal malignancies, etc. Bacteriological tests (smear/culture) almost fail owing to poor sensitivities and it is not always possible to get representative tissue samples for histopathological and cytological observations. In recent years, molecular tests i.e. nucleic acid amplification tests (NAATs), such as PCR/multiplex-PCR (M-PCR), nested PCR and GeneXpert are widely employed. Markedly, PCR/M-PCR and nested PCR exhibited reasonable good sensitivities/specificities, while GeneXpert revealed low sensitivity in most of the studies but high specificity, thus it could assist in differential diagnosis of intestinal TB and Crohn's disease. Further, novel molecular/immunological tests employed for pulmonary TB and other EPTB types were described and those tests can also be utilized to diagnose abdominal TB. Reliable and rapid diagnosis of abdominal TB would initiate an early start of anti-tubercular therapy and reduce the severe complications.

Differential Diagnosis of Abdominal Tuberculosis in the Adult-Literature Review

Tuberculosis (TB) is a public health issue that affects mostly, but not exclusively, developing countries. Abdominal TB is difficult to detect at first, with the incidence ranging from 10% to 30% of individuals with lung TB. Symptoms are non-specific, examinations can be misleading, and biomarkers commonly linked with other diseases can also make appropriate diagnosis difficult. As a background for this literature review, the method used was to look into the main characteristics and features of abdominal tuberculosis that could help with differentiation on the PubMed, Science Direct, and Academic Oxford Journals databases. The results were grouped into three categories: A. general features (the five forms of abdominal tuberculosis: wet and dry peritonitis, lymphadenopathy, lesions at the level of the cavitary organs, lesions at the level of the solid organs), B. different intra-abdominal organs and patterns of involvement (oesophageal, gastro-duodenal, jejunal, ileal, colorectal, hepatosplenic, and pancreatic TB with calcified lymphadenopathy, also with description of extraperitoneal forms), and C. special challenges of the differential diagnosis in abdominal TB (such as diagnostic overlap, the disease in transplant candidates and transplant recipients, and zoonotic TB). The study concluded that, particularly in endemic countries, any disease manifesting with peritonitis, lymphadenopathy, or lesions at the level of the intestines or solid organs should have workups and protocols applied that can confirm/dismiss the suspicion of abdominal tuberculosis.

Primary Esophageal Tuberculosis With Dysphagia

Tuberculosis is a common infection caused by Mycobacterium tuberculosis. Tuberculosis can affect many organ systems of the human body including the gastrointestinal tract. Esophageal involvement of tuberculosis is however rare.

A 60 years old male from Nepal with an occupational history suggestive of exposure to tuberculosis presented with dysphagia. He did not have any other complaints and his physical examination was unremarkable. An upper gastrointestinal endoscopic examination revealed an esophageal ulcer at 25 cm from incisors. Biopsy from the edge of the ulcer revealed granulomas with central caseous necrosis. A computed tomography scan of the chest and abdomen did not reveal additional lesions. Considering the higher prevalence of tuberculosis in the geographical area, he was started on an empirical antitubercular regimen. His dysphagia subsided within two weeks of starting therapy. A repeat upper gastrointestinal examination at six months of therapy revealed complete healing of the esophageal lesion.

In this case report, we review the symptomatology, diagnosis, and treatment of esophageal tuberculosis.

Asymptomatic peritoneal tuberculosis in a patient with a non-remitting fever and isolated pulmonary symptoms: a case report and literature review

Tuberculosis (TB) remains one of the leading causes of death globally. Although abdominal or peritoneal TB is a recognised site for extrapulmonary TB to manifest, the diagnosis is often delayed due to the non-specific nature of the presenting clinical features. We present the diagnostically challenging case of a 32-year-old patient with recurrent episodes of fever and a non-productive cough that was initially treated as community-acquired pneumonia with oral antibiotics. A computed tomography scan of the thorax was unrevealing, aside from a large volume of ascites within the partially imaged upper abdomen. The patient did not report any abdominal symptoms and the abdominal examination was unremarkable. Subsequently, a transvaginal ultrasound, a contrast-enhanced computed tomography scan of the abdomen and pelvis, and magnetic resonance imaging of the abdomen and pelvis confirmed a large volume of ascites in the absence of any definite aetiology. A peritoneal biopsy was required before the diagnosis of peritoneal TB was eventually confirmed. This case highlights the importance of considering peritoneal TB in patients presenting with treatment-resistant chest symptoms and persistent pyrexia of undetermined aetiology, even in the absence of abdominal signs and symptoms.

Extrapulmonary Tuberculosis—An Update on the Diagnosis, Treatment and Drug Resistance

Pathogenic Mycobacterium tuberculosis complex organisms (MTBC) primarily cause pulmonary tuberculosis (PTB); however, MTBC are also capable of causing disease in extrapulmonary (EP) organs, which pose a significant threat to human health worldwide. Extrapulmonary tuberculosis (EPTB) accounts for about 20–30% of all active TB cases and affects mainly children and adults with compromised immune systems. EPTB can occur through hematogenous, lymphatic, or localized bacillary dissemination from a primary source, such as PTB, and affects the brain, eye, mouth, tongue, lymph nodes of neck, spine, bones, muscles, skin, pleura, pericardium, gastrointestinal, peritoneum, and the genitourinary system as primary and/or disseminated disease. EPTB diagnosis involves clinical, radiological, microbiological, histopathological, biochemical/immunological, and molecular methods. However, only culture and molecular techniques are considered confirmatory to differentiate MTBC from any non-tuberculous mycobacteria (NTM) species. While EPTB due to MTBC responds to first-line anti-TB drugs (ATD), drug susceptibility profiling is an essential criterion for addressing drug-resistant EPTB cases (DR-EPTB). Besides antibiotics, adjuvant therapy with corticosteroids has also been used to treat specific EPTB cases. Occasionally, surgical intervention is recommended, mainly when organ damage is debilitating to the patient. Recent epidemiological studies show a striking increase in DR-EPTB cases ranging from 10–15% across various reports. As a neglected disease, significant developments in rapid and accurate diagnosis and better therapeutic interventions are urgently needed to control the emerging EPTB situation globally. In this review, we discuss the recent advances in the clinical diagnosis, treatment, and drug resistance of EPTB.