Bone and Joint Tuberculosis]
Bone and joint tuberculosis is a local manifestation of systemic infection by Mycobacterium tuberculosis. The bone and joint lesions focally removed by the physician are only the dominant lesions, and there may be occult lesions and extra-skeletal tuberculosis lesions in the same patient. Chemotherapy is essential to target all TB lesions in order to eradicate the TB bacterium from the whole body. It is not a substitute for complete surgical removal of the lesions alone. Therefore, chemotherapy for 2-6 weeks preoperatively and more than 9 months postoperatively is an important guarantee for the clearance of bone TB lesions.
[First-line anti-TB drugs].
Anti-TB drug therapy: The discovery of streptomycin in 1944, isoniazid in 1952 and rifampicin in 1965 represent three milestones of TB chemotherapy. The application of anti-tuberculosis drugs plays an important role in the treatment of tuberculosis, which can improve the efficacy and promote the healing of lesions. Currently, the commonly used first-line drugs include isoniazid (INH), rifampicin (RFP), pyrazinamide (PZA), ethambutol (EMB), and streptomycin (SM). Second-line drugs include butamycin, capreomycin, kanamycin, cycloserine, ethionamide, and p-aminoleucine.
Isoniazid (isoniazid, INH.H) is also known as rimifon (rimifon). It has the strongest early bactericidal effect and the best prevention of drug resistance. It is fast absorbed orally, easily penetrates into the chest, abdominal cavity, cerebrospinal fluid and joint fluid, and can penetrate into the cells, so it can also kill intracellular tuberculosis bacilli. The dosage for adults is 300mg per day, divided into 3 doses, but it is better to take it in one dose. The dosage for children is 10-20mg per kg of body weight per day. isoniazid is harmful to liver function and causes neuritis and psychiatric symptoms, so be careful to check liver function regularly while taking it.
Rifampicin (RFP,R) has the strongest sterilizing effect. It is absorbed through the intestinal tract after oral administration and can maintain high concentration in the blood for a long time, and can enter the cerebrospinal fluid through the blood-brain barrier. Rifampicin is more effective in the treatment of tuberculosis. The adult dose is 450-600mg per day, which can be taken in the early morning on an empty stomach, or divided into two doses. Rifampicin has side effects such as hepatic impairment, gastrointestinal reactions, skin reactions and flu-like reactions. Therefore, it is contraindicated in patients with serious impairment of liver function and biliary tract obstruction, and should be used with caution in the elderly, children and malnourished people.
Pyrazinamide (PZA,Z) has a specific sterilizing effect on intracellular tuberculosis flora in acidic environment, and the combination of PZA and RFP has the strongest sterilizing effect. Toxic effects are hepatic impairment and joint pain. Adults take 30~35mg/kg daily, 1.5g/day for those under 50kg, 2g/day for those over 50kg, 2.5g/day for those over 75kg, 20~25mg/kg/day for children.
Ethambutol (EMB,E) has a strong anti-tuberculosis effect and can diffuse into all tissues of the body. The dosage for adults is 750mg-1000mg per day, taken in one dose to obtain peak blood concentrations. Side effects include visual impairment. Should be discontinued when color vision is impaired early.
Streptomycin (SM,S) is a bacteriocidal agent, which only kills extracellular Mycobacterium tuberculosis. It is not easily absorbed orally, but can penetrate into various tissues by intramuscular injection, but cannot or rarely cross the blood-brain barrier. Long-term use may have auditory nerve damage and renal function damage, pay attention to the regular check of renal function. Dose for adults, 1g per day in 1-2 intramuscular injections. The dosage for children is 15-30mg/kg body weight per day. 3-4 months resistance increases.
[Standard short-term chemotherapy].
The principles of anti-tuberculosis drug use are early, adequate, combined, and regular drug use. Mitchison proposed that the tuberculosis bacilli in the lesion can be divided into four different metabolic states, which have different responses to chemotherapy.
(1) Rapidly multiplying bacilli: all can be killed by SM, INH, RFD, or even INH alone.
(2) Intermittent multiplying bacteria (in cheese): RFP and INH are effective.
(3)Chronic multiplying bacteria: mostly exist in giant hobby cells, general drugs can’t destroy it quickly, need a certain course of treatment. pza is the most effective.
(4) Completely dormant bacteria: low number, RFP is effective.
The combination of INH, RFP and PZA constitutes the standard short course chemotherapy regimen (9HRZ), which can play their respective roles and synergistic effects, acting on three different metabolic flora and intra- and extracellular flora, and the drugs achieve bactericidal and sterilizing effects at different pH values, thus greatly shortening the treatment time, which can be regarded as highly effective, sensitive, low toxicity and economical drugs.
(9HRZ) indicates a 9-month course of treatment, one tablet of each isoniazid (INH,H) + rifampicin (RFP,R) + pyrazinamide (PZA,Z), taken daily in the early morning. Observe the toxic and side effects during administration. Check regularly and adjust promptly. Of course, there are also regimens such as 9HRZ4E, 2SHRZ/6H3R3T and 4SHRE/5HRE.
Surgical treatment under the control of anti-tuberculosis drugs and timely and thorough removal of tuberculosis lesions can greatly shorten the course of treatment, prevent the occurrence of deformity or paraplegia, and greatly improve the cure rate of bone tuberculosis. At the same time, the indications for surgery should be emphasized, and surgery should not be abused.
Blood sedimentation to see changes]
Through the change of blood sedimentation, we can observe the change of tuberculosis disease and its curative effect. The acceleration of blood sedimentation indicates that the disease is relapsing and active; when the disease improves or becomes quiescent, the blood sedimentation also gradually recovers.