M. Bovis, M. Africanum, M. Tuberculosis
Stage I-macrophage ingests
Stage II-reproduction leads to lysis, repeat, to tubercle, transmitted to lymph nodes, kidneys, long bones, meninges, apical portions of lungs
Stage III-2-3 weeks. Cd4 kill Tb forming granulomas. Can survive in the granuloma. Walled off by epitheloid cells.
Stage IV-Reactivation-Erosion of bronchial walls. In the immunocompetent 5% will progress in the first three years then another 5% later in life.
Cough, sputum, night sweats, weight loss
Complication-pneumo, empyema, endobronchial spread, superinfection of cavities (aspergillus), massive hemoptysis,
Radiology
C-XR: primary infiltrate shows increased hilar or mediastinal nodes, Ghon focus is a healed calcified scar. If associated c large hilum then Ranke Complex. Post-primary upper lung infiltrate or consolidation+-cavitation. Irregular angular lesions c strands extending towards hilum.
Detection of TB with normal chest radiograph (Chest 1999;115:445) Only 1 out of 518 patients was smear + and cxr neg, though 22 were cx + (non-infectious)
Dx c sputum or bronch
PPD + 3-8 weeks after infection .1 cc dose
Back to topExtrapulmonary
Lymphadenitis (Scrofula)-most commonly cervical, discrete rubbery mass, Excise and ripe
Pleural effusion or empyema
Spinal (Potts)-back pn or stiffness. Also hip or knee
Renal-sterile pyuria, can spread to reproductive tract
Miliary-usually can see on XR
Meningitis-malaise, HA, fever, One LP only 37% sensitive
Intracranial TB
GI-anywhere in the tract
Peritonitis-exudative c lymphocytes
Massive Hemoptysis
Rx: can begin rx immediately as it will not affect the testing
Rifampin, INH, Pyrazinamide, Ethambutol (Streptomycin, Levaquin)
INH Overdose leads to seizures. Treat c pyridoxine gram for gram or 5g empiric
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