PubMed Health⌕ Search

PubMed · 15086014

Primary nasal tuberculosis: a case report.

Abstract

During the past 2 decades, tuberculosis--both pulmonary and extrapulmonary--has re-emerged as a major health problem worldwide. Nasal tuberculosis--either primary or secondary to pulmonary tuberculosis or facial lupus--is rare, but it should be considered in the differential diagnosis of nasal granulomas. We describe a case of primary nasal tuberculosis in an adult male who presented with a polypoid lesion in one nasal cavity. The diagnosis was based on histopathology and the patient's successful response to antituberculous drug treatment. Given the rising incidence of tuberculosis, it is prudent that otolaryngologists remain cognizant of this infection as a potential cause of unusual lesions in the head and neck.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Ravi C Nayar, Juma Al Kaabi, Kanchanmala Ghorpade. 2004. Primary nasal tuberculosis: a case report.. https://pubmed.ncbi.nlm.nih.gov/15086014/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Mechanism of thioamide drug action against tuberculosis and leprosy.

Thioamide drugs, ethionamide (ETH) and prothionamide (PTH), are clinically effective in the treatment of Mycobacterium tuberculosis, M. leprae, and M. avium complex infections. Although generally considered second-line drugs for tuberculosis, their use has increased considerably as the number of multidrug resistant and extensively drug resistant tuberculosis cases continues to rise. Despite the widespread use of thioamide drugs to treat tuberculosis and leprosy, their precise mechanisms of action remain unknown. Using a cell-based activation method, we now have definitive evidence that both thioamides form covalent adducts with nicotinamide adenine dinucleotide (NAD) and that these adducts are tight-binding inhibitors of M. tuberculosis and M. leprae InhA. The crystal structures of the inhibited M. leprae and M. tuberculosis InhA complexes provide the molecular details of target-drug interactions. The purified ETH-NAD and PTH-NAD adducts both showed nanomolar Kis against M. tuberculosis and M. leprae InhA. Knowledge of the precise structures and mechanisms of action of these drugs provides insights into designing new drugs that can overcome drug resistance.

Antitubercular Agents↗

EthA, a common activator of thiocarbamide-containing drugs acting on different mycobacterial targets.

Many of the current antimycobacterial agents require some form of cellular activation unmasking reactive groups, which in turn will bind to their specific targets. Therefore, understanding the mechanisms of activation of current antimycobacterials not only helps to decipher mechanisms of drug resistance but may also facilitate the development of alternative activation strategies or of analogues that do not require such processes. Herein, through the use of genetically defined strains of Mycobacterium bovis BCG we provide evidence that EthA, previously shown to activate ethionamide, also converts isoxyl (ISO) and thiacetazone (TAC) into reactive species. These results were further supported by the development of an in vitro assay using purified recombinant EthA, which allowed direct assessment of the metabolism of ISO. Interestingly, biochemical analysis of [(14)C]acetate-labeled cultures suggested that all of these EthA-activated drugs inhibit mycolic acid biosynthesis via different mechanisms through binding to specific targets. This report is also the first description of the molecular mechanism of action of TAC, a thiosemicarbazone antimicrobial agent that is still used in the treatment of tuberculosis as a second-line drug in many developing countries. Altogether, the results suggest that EthA is a common activator of thiocarbamide-containing drugs. The broad specificity of EthA can now be used to improve the activation process of these drugs, which may help overcome the toxicity problems associated with clinical thiocarbamide use.

Antitubercular Agents↗