Diseases List

ID 99
Name TUBERCULOSIS
Cause
Signs Symptoms
Diagnosis
Investigations
Management
Introduction
History
Etiology
Clinical Features
Preventions
Treatment Treatment of Tuberculosis: A. General measures: 1. Bed rest- untill the acute symptoms have subsided, specially for bone tuberculosis. 2. Isolation- untill the sputum positive cases are negative. 3. High calorie, high protein diet with vitamins. 4. For cough- Codeine phosphate 8-15 mg orally 4-6 hourly if necessary. B. Anti-tuberculosis chemotherapy: First-line drugs2- Isoniazid, rifampicin, pyrazinamide, ethambutol, streptomycin, rifabutin, thiacetazone Second-line drugs2- Clarithromycin or azithromycin, ofloxacin or ciprofloxacin, protionamide or ethionamide, cycloserine, capreomycin, para-aminosalicylic acid (PAS). 1. INH- Children, 10mg/kg/day. Adult, 200-300mg/day. Intermittent regimen, 15mg/kg Miliary/meningitis, 10-12mg/kg. + Pyridoxine 10mg/day (in all cases). 2. Rifampicin- Children- 10-20mg/kg/day. Adult, wt > 50kg- 600mg (max.) Adult, wt < 50kg- 450mg (max.) 3. Pyrazinamide- Children 20-35mg/kg/day. Adult wt > 45kg, l.5gm (max.) Adult wt < 45kg, 2.0gm (max.) N.B: Pyrazinamide, as it diffuses well into the cerebrospinal fluid, is particularly useful in the treatment of tuberculous meningitis. 4. Ethambutol- Children & adults: initial 8 wks, 25mg/kg/day. Subsequently, 15mg/kg/day In renal failure, according to serum level. 5. Streptomycin- Children- 30mg/kg/day. Adults under 40 years and weighing more than 45kg, Igm. Adults 40-60 years or weighing less than 45kg- 0.75gm. Intermittent regimens, 0.75-Igm. Adults over 60 years or in patients with renal failure, the dose of streptomycin should be reduced according to serum levels. N.B: Streptomycin, now a day used very rarely in patients with multiple drug resistance or hypersensitivity. C. Steroid therapy- Corticosteriod may be used in conjunction with anti-tuberculous drugs, such as in- a. Milliary tuberculosis. b. Acute and severely ill tuberculous patient at the onset of chemotherapy. c. Corticosteroids prevent or minimise the formation of fibrous tissue and is valuable in the treatment of tuberculosis affecting the pleura, pericardium, intrathoracic and superficial lymphnodes, the eye and meninges or in ureteric obstruction. Dose: Prednisolone 10-20mg daily in 2-3 divided doses for 6-12 weeks. N.B. 1. During impaired hepatic function, anti-tuberculosis treatment should be stopped and to be started later on when liver function tests become normal. 2. In impaired renal function, patient can be safely treated by reducing the doses of streptomycin or changing it. 3. During pregnancy all main drugs except streptomycin can be used. Side-effects of T.B drugs: 1st line drugs Complications INH - Hypersensitivity, polyneuropathy (can be prevented by Pyridoxine), lack of mental concentration. Rifampicin- Nausea, abdominal pain, hyperse-nsitivity hepatitis, vasculitis, fever, skin flushing, breathlessness and wheeze (intermittent regimens only). Rifampicin should not be given again to any patient in whom it has caused vasculitis. It colours the urine pink. Drug interactions (see appedix.) Pyrazinamide - Hepatitis, gout, hypersensitivity. Ethambutol- Optic neuritis, hypersensitivity. Streptomycin- Vestibular disturbance, deafness (rare) (8th nerve), Hypersensitivity. 2nd line of drugs Ethionamide - Nausea, vomitig, hepatitis. Cycloserine - Neurotoxicity. PAS - Nausea, vomiting, skin rash. Treatment regimens now used: Now a day two regimens, a short-course 6-month regimen and a long-course 9- (or 12-) month regimen are effectively used in treating pulmonary tuberculosis. Indication of 6 month regimen: 1. Patients with new-onset or previously untreated pulmonary tuberculosis. 2. Uncomplicated pulmonary or extrapulmonary tuberculosis. 3. HIV-negative patient. Indication of 9-12 month regimen: 1. Pulmonary tuberculosis with meningeal involvement. 2. HIV coinfection. 3. Substitution of second-line drug in the regimen due to intolerance of first-line drug. 4. Relapses and treatment failures. A. 6 month regimens: Initial phase: (2 months) INH + Rifampicin + Pyrazinamide + Ethambutol or Streptomycin. (Fourth drug of this regimen can be omitted in patients in whom isoniazid resistance is unlikely). Continuation phase: (4 months) INH + Rifampicin. B. 9-12 month regimens: Initial phase (2 months) INH + Refampicin + Pyrazinamide or Streptomycin Continuation phase (7 or 9 month) INH + Refampicin. N.B: Pyridoxine should always be added in addition to isoniazid to prevent the peripheral neuropathy 1 tablet (10 mg.) t.d.s for same period. C. Regimens for special situations: 1. Patients with a history of previous treatment: Therapy must be started with 4 drugs (see above) until the sensitivity results are available. If the mycobacteria are found susceptible to isoniazid and rifampin, the second phase of therapy to be continued with this two drugs for a minimum of 4 additional months (or 7 months if is required). 2. Treatment of drug-resistant tuberculosis: a) Tuberculosis resistant to only isoniazid: A 6-month regimen of rifampin, Pyrazinamide, and ethambutol or streptomycin or a 12-month regimen of rifampin and ethambutol should be given. If isoniazid resistance develops during a course of 9-month regimen without pyrazinamide, isoniazid should be discontinued and rifampin and ethambutol should be continued for a minimum of 12 months. If ethambutol is not the part of initial regimen, sensitivity test should be repeated and two other susceptible drugs should be added. b) Multiple drug resistance tuberculosis (MDRT): The treatment of ‘multiple drug resistance tuberculosis’ is very complex, and depends on the susceptibility test of the isolate and status of the individual. The patient must be admitted in the hospital and to be kept in isolation room until becomes non-infectious. Five or more drugs are advised in the initial regimen. Most patients are found resistant to at least isoniazid and rifampicin and require a minimum of three drugs to which the organism is sensitive. These susceptible drugs are continued until culture has become negative for MTB, and then a two-drug regimen is continued for at least another 12 months. Recently, the MDRTB patients are recommended to treat under the ‘directly observed treatment (DOT)’ plan. 3. Treatment of tuberculosis in pregnant or lactating women: During pregnancy all main drugs can be used except streptomycin because, it can cause congenital deafness. The use of pyrazinamide is also not risk-free, as its teratogenic effect yet not clearly defined, therefore, it should only be advised in cases, where resistance develops to other frist-line drugs. 4. Treatment of tuberculosis in HIVpositve patients: These patients must be treated in the Centers for Disease Control and prevention (CDC), and directly observed therapy (DOT) should be used for all HIV-positive tuberculosis patients, under the care of experts on both tuberculosis and HIV disease. Directly observed therapy (DOT):1'2 It is known that, patient’s nonadherence & noncompliance to antituberculous treatment are the major causes of treatment failure, development of drug resistance & continued transmission of the disease. In this context, directly observed therapy (DOT), a concept has been developed to improve the patient’s adherence & compliance in the management of tuberculosis treatment. In this, a health care worker will look-after all aspects of an individual taking antituberculous medications in the home, clinic, hospital, or elsewhere. Directly observed therapy (DOT) is recommended for- 1. All patients with drug-resistant tuberculosis. 2. Patients receiving intermittent (twice- or thrice-weekly) therapy. 3. Patients who are unlikely to comply to antituberculous treatment such as-alcoholics, injection drug users, mentally ill patients, 4. Patients failing previous therapy. 5. HIV-positive tuberculosis patients. Currently WHO recommends DOT therapy for all patients with tuberculosis at a global level. Chemoprophylaxis of TB: INH 5mg/kg by mouth daily for 1 year shoud.be considered in- - non vaccinated tuberculin positive children under 3 years. - unvaccinated contacts who have recently become tuberculin positive. - immunocompromised patient. - adolescents with high degree of tuberculin sensitivity. INH 5mg/kg by mouth daily for 6 wks should be considered in- - infants of highly infectious parents. Extrapulmonary Tuberculosis Common sites of extrapulmonary tuberculosis are lymph nodes, skin, gastrointestinal organs and soft tissues; other sites include- central nervous system (meninges & brain), bones & joints, pericardium & genitourinary system. The treatment regimens of extrapulmonary tuberculosis are almost same as pulmonary tuberculosis. But, some authorities recommend 9-months therapy when miliary, meningeal, or bone and joint disease is present. In cases of skeletal tuberculosis early surgical drainage and debridement of necrotic bone tissues are helpful.
Complications
Prognosis
Types
Classification
Observation
Pathology
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406