Disease caused by Mycobacterium ulcerans. First described by MacCallum in 1948, but the name came from Buruli country in Uganda. The third most common Mycobacterium, that affected more than 30 countries.
Mode of transmission Mode of transmission is not entirely known evidence suggest that insects are aquatic bugs belong to the genus Noucaris and Diplonychus may transmit the microbe. Person to person transmission are not clearly supported. Trauma during swimming.
Pathogenesis Once inoculated into the subcutaneous tissue the organisms proliferates and elaborates a toxin that has affinity for fat cells. The toxin called Mycolactone which cause local immunosuppression in infected tissue. The most affected are children under the age of 15 years, mortality is low but disability is high(66%) affected region mostly the upper extremities. The resulting necrosis then provides a favorable milieu for further proliferation of the organisms. Clinically the disease manifests as Papules, Nodules, Plaques, Odematous Forms and Ulcers.
Diagnosis Clinical: depending on the clinical ground Laboratory: any two of the following finding are required: Acid fast bacilli in a smear stained with Ziehl Neelsen. Positive culture of M.ulcerans ( required 6-8 weeks or longer at 30-33ċ, produce Rough domed, lemon yellow colony on L.J medium) Histopathological study of excisional biopsy specimen. Positive PCR for DNA from M. ulcerans.
Treatment Drug treatment: several antimicrobial agent have in vitro activity, but no single agent has been proven to regularly useful in treatment. Agent used include Rifampicin, Rifabutin, Clarithromycin,Azithromycin,Streptomycin, and Amikacin. Combination therapy are mostly used. Surgical treatment: need prolong hospital stay (100 days).