Program-wide review and follow-up of erythema Induratum of Bazin and tuberculosis-associated ocular inflammation management in a TB low-incidence setting: need for improved treatment candidate selection, therapy standardization, and care collaboration.

BACKGROUND: Erythema induratum of Bazin (EIB) - nodular vasculitis associated with Mycobacterium tuberculosis (TB) - and Tuberculosis-Associated Ocular Inflammation (TB-AOI) represent uncommon manifestations of TB. There is limited data and a lack of diagnostic and treatment standards for these conditions. METHODS: Eleven-year retrospective review of EIB and TB-AOI cases managed in a provincial TB program with prospective phone-based follow-up of anti-tubercular therapy (ATT) recipients. Presumptive TB-AOI and EIB diagnoses were determined by ophthalmologist or dermatologist assessments correlated with positive tuberculin skin test and/or QuantiFERON-TB Gold, along with pathologic criteria in EIB cases. RESULTS: Of 21 EIB and 20 TB-AOI cases that received ATT, 13 and 11, respectively, were reached for follow-up. The majority of EIB and TB-AOI cases were female and immigrated from TB high-burden countries. Median durations of pre-diagnosis symptoms were 2 and 0.8 years (IQR 2.5 & 1.1) for EIB and TB-AOI cases, respectively. Overall, 14 different ATT regimens were used for a median duration of 6 months (range 5-9). ATT related adverse events resulting in treatment discontinuation occurred in 14% of EIB and 10% of TB-AOI cases. On last follow-up, 76% of EIB and 42% of TB-AOI had improvement or resolution of disease. CONCLUSION: EIB and TB-AOI were uncommon presentations receiving variable therapy. While treatment response was modest for EIB cases, TB-AOI cases had sub-optimal treatment outcomes. The unique diagnostic and management challenges presented by these conditions in TB low-incidence settings highlight a need for improved treatment candidate selection, therapy standardization, and cross-specialty medical collaboration.

New treatment options for multidrug-resistant tuberculosis.

Despite the development of effective treatments, tuberculosis (TB) remains a major health problem. TB continues to infect new victims and kills nearly 2 million people annually. The problem is much greater in resource-limited countries but is present worldwide. Inadequate public health resources, cost, the obligatory long treatment period, and adverse drug effects contribute to treatment failures and relapses. Drug-resistant Mycobacterium tuberculosis (MTB) strains arise spontaneously and are propagated by inadequate treatment. According to World Health Organization global data, 17% of MTB strains in new, previously untreated cases are resistant to at least one drug. Approximately, 3.3% of new MTB cases are resistant to both isoniazid and rifampin, also called multidrug resistant (MDR), and rates of MDR-TB are greater than 60% in previously treated patients in some countries. Approximately 5% of cases of MDR-TB are also resistant to fluoroquinolones and to injectable drugs, and are called extensively drug resistant (XDR). Recently, XDR strains have been isolated that are also resistant to all standard second-line anti-TB medications. Successful drug treatment of TB with complex resistance profiles is virtually impossible with currently available drugs. There is a desperate need for new compounds that cure strains resistant to currently available drugs and for drugs that are better tolerated and will shorten treatment regimens. In the short term, new strategies for the management of drug-resistant TB with currently available drugs are being explored. These include the use of high-dose isoniazid, substitution of rifabutin in a small proportion of rifampin-resistant cases, linezolid, fluoroquinolones, and phenothiazines. A number of novel drugs are undergoing clinical testing and will hopefully be available in the near future. These include the newer oxazolidinones, diarylquinolines, nitroimidazopyrans, ethenylenediamines, pyrroles, and benzothiazinones.