Clinical Picture

Step-by-step approach

• Night sweats, cough, hemoptysis, contact with a TB patient, past incompletely treated TB
• Risk factors for immunosuppression: HIV status (mandatory test), diabetes, chronic steroid/immunosuppressant use, malnutrition, alcohol use
• Lymphadenopathy, hepatosplenomegaly, skin lesions
• Fundoscopy for choroidal tubercles - quick, often overlooked, near-pathognomonic bedside sign of miliary TB

• CBC (miliary TB can cause pancytopenia from marrow involvement), LFTs (TB hepatitis is common), RFT, ESR/CRP, HIV ELISA, HbA1c/blood sugar, LDH

• Ascitic fluid: SAAG, total protein, cell count, cytology, AFB smear/culture, Xpert MTB/RIF (CBNAAT), and adenosine deaminase (ADA) - ascitic ADA has high sensitivity/specificity for tuberculous peritonitis (Sleisenger & Fordtran's Gastrointestinal and Liver Disease; Murray & Nadel's Textbook of Respiratory Medicine). CA-125 may be raised in TB peritonitis and can mimic ovarian/peritoneal malignancy - don't let a raised CA-125 alone push you toward malignancy.
• Pleural fluid: Light's criteria (expect exudate, lymphocyte-predominant), glucose, cytology, AFB smear/culture, Xpert MTB/RIF, and pleural ADA (>40 U/L strongly supports TB pleuritis) - Goldman-Cecil Medicine; Henry's Clinical Diagnosis and Management by Laboratory Methods.

• Sputum (even if non-productive, use induced sputum) for AFB smear, culture, and Xpert MTB/RIF
• If sputum is negative/unobtainable: bronchoscopy with BAL and transbronchial lung biopsy - given the diffuse miliary pattern, TBLB has a good yield for granulomas and AFB culture

• Pleural biopsy (Abrams needle or CT/USG-guided) for histopathology (caseating granulomas) and culture - higher yield than fluid cytology/AFB alone
• Laparoscopic peritoneal/omental biopsy if ascites persists undiagnosed - considered near gold-standard for TB peritonitis (shows "violin-string" adhesions, whitish tubercles studding the peritoneum) and simultaneously excludes peritoneal carcinomatosis
• Bone marrow aspirate/biopsy with AFB culture - especially useful if there is cytopenia; high yield in disseminated TB
• Liver biopsy if hepatomegaly/deranged LFTs

• Contrast CT abdomen: look for necrotic mesenteric/para-aortic lymph nodes, hepatosplenic micro-abscesses, peritoneal thickening/enhancement (favors TB) versus omental caking/nodularity (favors carcinomatosis)
• USG-guided aspiration of any accessible node

• Tuberculin skin test / IGRA - low sensitivity in disseminated TB due to anergy; a negative result does not rule out miliary TB

• If the patient deteriorates before a tissue/microbiological diagnosis is secured, and pre-test probability is high (endemic region, compatible imaging, no clear alternative), collect all possible samples for AFB smear/culture/PCR first, then start empirical anti-tubercular therapy. A clinical and radiological response within 4-6 weeks supports the diagnosis; failure to respond should prompt reconsideration of the diagnosis (per Harrison's Principles of Internal Medicine, FUO chapter).

Differentials to keep on the list until excluded

• Disseminated fungal infection (histoplasmosis, cryptococcosis) - especially if immunocompromised
• Sarcoidosis (less commonly causes this degree of ascites)
• Lymphoma or miliary metastatic malignancy with serosal spread
• Peritoneal carcinomatosis (send fluid cytology in every case)

Bottom line

CT / CXR Interpretation - Rukmani Bai Khatik, 76F, Kyphoscoliotic, Known Sliding Hiatus Hernia

Findings

• Markedly rotated, kyphoscoliotic bony thorax with asymmetric rib cage.
• A large, rounded, mottled/bubbly opacity is seen overlying the right cardiophrenic-retrocardiac region, obscuring the right heart border - the lucent, bubbly internal pattern represents air within herniated gastric rugal folds rather than a solid mass.

• A large, well-defined, thin-walled structure with mixed fluid/soft-tissue and gastric-fold-lined gas content lies immediately posterior/adjacent to the heart in the lower posterior mediastinum.
• On sequential caudal slices this structure is seen in direct continuity across the esophageal hiatus with the intra-abdominal stomach - confirming it is herniated stomach, not a mediastinal mass.
• Severe kyphoscoliotic distortion of the thoracic cage (rotated vertebral bodies, crowded/asymmetric ribs) is present throughout.

• The adjacent lung (right lower/middle lobe territory) shows compressive atelectasis/crowding from mass effect of the hernia sac; no discrete intrapulmonary nodule or infiltrate is seen - the apparent "opacity" on the CXR is entirely accounted for by the herniated stomach, not primary lung pathology.

Impression

• Grainger & Allison's Diagnostic Radiology, Fig. 20.23C

Points to actively check on the images / clinically

1. Rule out gastric volvulus - look for organoaxial/mesenteroaxial rotation of the herniated stomach, a "double air-fluid level," or an abrupt transition point at the hiatus. This is a recognized complication of large intrathoracic stomach and can progress to a surgical emergency (violent retching with minimal vomitus, epigastric pain, inability to pass an NG tube).
2. Wall integrity/perfusion of the herniated gastric segment - wall thickening, lack of contrast enhancement, or pneumatosis would suggest ischemia/strangulation.
3. Degree of lung compression - relevant given this patient already has restrictive physiology from kyphoscoliosis; the added extrinsic compression from a large hernia can meaningfully worsen respiratory reserve.
4. Other herniated contents - confirm whether only stomach, or also colon/omentum/spleen, has migrated through the hiatus (common in large paraesophageal hernias).
5. Clinical correlation for reflux, dysphagia, early satiety, postprandial breathlessness or chest discomfort, and check hemoglobin (chronic mucosal ulceration at the hernia neck - "Cameron lesions" - can cause iron-deficiency anemia).

Practical implication