Extrapulmonary TB

Handwritten video lecture on Extrapulmonary TB for USMLE Step 1 and USMLE Step 2. Will be discussing pathophysiology, signs and symptoms, diagnosis and treatment.

Tuberculosis (TB) can affects sites outside the lung. The most common sites tuberculosis (TB) can occur outside the lungs is the lymph node, pleura, genitourinary tract, bones and joints, meninges, peritoneum and pericardium. Now extrapulmonary Tuberculosis (TB) is more common due to the presence of HIV.

LYMPHATIC TUBERCULOSIS (TB)
Most commonly affect the posterior cervical lymph node and supraclavicular lymph node known as scrofula. Usually presents as painless swelling. May have a fistulous tract and casseous material.

PLEURAL TUBERCULOSIS (TB)
Due to hypersensitivity reaction or direct spread. Generally associated with dullness and decrease breath sounds consistent with pleural effusion. Thoracocentesis will show straw colored fluid high in protein but low in glucose. Generally alkaline fluid with ADA and lysozyme positive. AFB Microscopy and AFB culture and biopsy is helpful in diagnosis.

GENITOURINARY TUBERCULOSIS (TB)
Patient will complain of dysuria, frequency, Nocturia and hematuria. If upper urinary tract may complain of flank abdominal pain. If asyptomatic may present wit hydronephrosis strictures. Urinalysis will show pyruia, hematuria without bacteria. IV pyelography and CT /MRI are also necessary to diagnosis deformities. Male will have epididymis, orchitis, prostitis.

BONE AND JOINT TUBERULCOSIS (TB)
If affects the vertebral column then known as Pott’s Disease. Tenderness at area of infection. X-ray CT is diagnostic.

MENINGITIS
Most common in children and HIV. Present with headache mental changes and neck rigidity with underlying fever and malaise. Base of the brain will cause effect on cranial nerve palsies, such as oculomotor nerve palsies. Patient may get coma hydrocephalus. CSF analysis shows leukocyte, low glucose, low protein, CSF Smear yields AFB. Culture is gold standard and PCR has 80 percent sensitivity.

GASTROINTESTINAL TUBERCULOSIS (TB)
Due to swallowing, Hematogenous spread or cow’s milk (Mycobacterium bovine). Symptoms abdominal pain, swelling, obstruction, hematochezia, palpable mass, fever, night sweats, weight loss.

PERITONITIS TUBERCULOSIS (TB)
Due to rupture, Hematogenous spread, intraabdominal organs. Paracentesis shows exudative fluid, high protein, and high WBC.

OTHER FORMS OF EXTRAPULMONARY TUBERUCLOSIS (TB)
Pericardial
Eye – chiorioretinitis, uveitis, panopthalmitis
Ear – TM perforation, hearing loss
Cutaneous, mastitis
Adrenal insufficiency
Congenital TB and Transplacental TB