Patient description: Patient A is a 30-year-old male who was admitted to the hospital after 10 days of cough, profuse nocturnal sweating and loss of appetite. He had traveled to India 1 months ago and has not any positive history of TB vaccination. He is a previously healthy man, working as an engineer in a high tech company. He doesn't smoke o use any illicit drugs. He was febrile (38 c) with heart rate of 115 b/min, respiratory rate of 22, BP of 125/75 mmHg and O2 sat of 97%. Chest X-ray showed infiltrate in the middle of left lung with diameter of 1.8 cm with signs of cavitation. The sputum smear revealed positive sputum culture for Mycobacterium tuberculosis which are sensitive of the first-line TB drugs (isoniazid, streptomycin, rifampicin and ethambutol). Lab study is reported bellow: Hgb: 13 g/dl WBC: 14000 /mm3 Plt: 300000 /ml AST: 13 U/L ALT: 15 U/L Alk P: 53 U/L Bill total: 0.6 mg/dl Na: 137 mEq/l K: 4 mEq/l Creatinine: 0.5 mg/dl BUN: 10 mg/dl ESR: 120 mm/hr

Clinical trial eligibility criteria: eligible ages (years): 20.0-999.0,  Tuberculosis Multi-Drug Resistant Tuberculosis Male and females age 20 and above 2. Signs or symptoms of tuberculosis (i.e., cough that has lasted 3 weeks or longer, hemoptysis, chest pain, fatigue, weight loss, night sweats) 3. Subjects with documented AFB smear-positive pulmonary tuberculosis at screening to NMTH 4. Radiographic evidence of tuberculous disease of the lung(s) 5. TB isolate resistant to at least isoniazid and rifampicin 6. Drug Susceptibility Testing (DST) results known for ofloxacin (can be either sensitive or resistant) 7. Ability and willingness to give written or oral informed consent 8. Willingness to be an inpatient at NMTH for, at minimum, the duration of study drug/placebo treatment 9. Willingness to have samples stored 10. Available for follow-up visits  People who are unwilling or unable to abstain from alcohol consumption for the study drug treatment duration (8 weeks) 2. Women of childbearing potential, who are pregnant, breast feeding, or unwilling to avoid pregnancy by the use of appropriate contraception including oral and subcutaneous implantable hormonal contraceptives, condoms, diaphragm, intrauterine device (IUD), or abstinence from sexual intercourse at study screening and during the study drug/placebo treatment (two months with allowed stops) (Note: Prospective female participants of childbearing potential must have negative pregnancy test (urine) within 48 hours prior to study entry.) 3. Subjects with pan resistant isolates 4. Presently taking 2nd -line agents started more than 14 days prior to initial FDG-PET scan 5. People with any of the following in their current medical assessment: 1. Absolute neutrophil count less than 1000 cells/mL 2. White Blood Cell count (WBC) less than 3.0 X 10(3)/microliter 3. Hemoglobin less than 7.0 g/dL 4. Platelet count less than 75,000 cells/mm(3) 5. Serum creatinine greater than 2.0 mg/dL 6. Aspartate aminotransferase (AST or SGOT) greater than 100 IU/L 7. Alanine aminotransferase (ALT or SGPT) greater than 100 IU/L 8. Total bilirubin greater than 2 mg/dL 9. Moderate or severe peripheral neuropathy 10. HIV-1 or HIV-2 infection 11. History of systemic lupus erythematosus, rheumatoid arthritis, or other connective tissue disease 6. Terminal illness with impending mortality 7. History of allergy or serious adverse reaction to metronidazole or placebo formulation used in this study 8. The use of any of the following drugs within 30 days prior to study or anticipated use of these drugs within the next 60 days: 1. Systemic cancer chemotherapy 2. Systemic corticosteroids 3. Systemic investigational agents 4. Antiretroviral medications 5. Growth factors 6. HIV vaccines 7. Immune globulin 8. Interleukins 9. Interferons 9. The need for ongoing therapy with warfarin, phenytoin, lithium, cimetidine, disulfiram, ergot derivatives, cholestyramine, fosphenytoin, carbamazepine, cyclosporine, tacrolimus, sirolimus, amiodarone or phenobarbital while on study drug. 10. Any other serious systemic illness requiring treatment and/or hospitalization until subject either completes therapy or is clinically stable on therapy for at least 14 days prior to study entry 11. Unwilling to be an inpatient at NMTH for greater than or equal to 2 months 12. Any condition that the investigator believes would warrant