In severe chronic kidney disease (GFR<30), the EMB dose should be halved (or avoided altogether). The PZA dose is 20 mg/kg/day (UK recommendation) or three-quarters the normal dose (US recommendation), but not much published evidence is available to support this. When using 2HRZ/4HR in patients on dialysis, the drugs should be given daily during the initial high-intensity phase. In the continuation phase, the drugs should be given at the end of each haemodialysis session and no dose should be taken on non-dialysis days. HIV
In patients with HIV, treatment for the HIV should be delayed until TB treatment is completed, if possible. The current UK guidance (provided by the British HIV Association) is

CD4 count over 200—delay treatment until the six months of TB treatment are complete. CD4 count 100 to 200—delay treatment until the initial two-month intensive phase of therapy is complete
CD4 count less than 100—the situation is unclear and patients should be enrolled in clinical trials examining this question. There is evidence that if these patients are managed by a specialist in both TB and HIV then outcomes are not compromised for either disease.If HIV treatment has to be started while a patient is still on TB treatment, then the advice of a specialist HIV pharmacist should be sought. In general, there is no significant interactions with the NRTIs. Nevirapine should not be used with rifampicin. Efavirenz may be used, but dose used depends on the patients weight (600 mg daily if weight less than 50 kg; 800 mg daily if weight greater than 50 kg).
Implementation of DOTS-Plus requires the capacity to perform drug-susceptibility testing (not routinely available even in developed countries) and the availability of second-line agents, in addition to all the requirements for DOTS. DOTS-Plus is therefore much more resource-expensive than DOTS, and requires much greater commitment from countries wishing to implement it. Community engagement is a new approach that is being initiated alongside the DOTS individualized treatment. By creating a community for health workers to give support to patients and hospital faculty, the DOTS-plus model also incorporates psychological structural support treatments to help accommodate patients to ensure completion of treatment. Treatment with the new strategy is a total duration of 18–24 months.Monthly surveillance until cultures convert to negative is recommended for DOTS-Plus, but not for DOTS. If cultures are positive or symptoms do not resolve after three months of treatment, it is necessary to re-evaluate the patient for drug-resistant disease or nonadherence to drug regimen. If cultures do not convert to negative despite three months of therapy, some physicians may consider admitting the patient to hospital so as to closely monitor therapy. Extra-pulmonary tuberculosis
Tuberculosis not affecting the lungs is called extra-pulmonary tuberculosis. Disease of the central nervous system is specifically excluded from this classification. The United Kingdom and the World Health Organization (WHO) recommendation is 2HREZ/4HR; the US recommendation is 2HREZ/7HR.