Melioidosis is a relatively rare infectious disease of musculoskeletal system. It has got widespread occurrence and it is found in soil of almost all the states of India. However, it is reported more from southern states.
8–10 India's rural population lives in close proximity to agricultural land and is quite susceptible to this neglected killer disease. It occurs in our patients with far more frequency than imagined. But it is underreported in India because of: (i) lack of awareness of disease (ii) low index of suspicion and (iii) under-recognition of disease.
14,15 It should be suspected by a microbiologist on isolation of a gram negative bacillus, which is oxidase positive, bipolar staining which is gentamycin resistant.
It mostly affects the respiratory system with soft tissues abscesses. It can be ignored easily by laboratory technicians or clinicians if not aware of it. It occurs in persons with concur rent diabetes, renal failure, thalassemia and immunocompromised status. It is introduced into the body by inoculation via skin or inhalation.
14 Sexual transmission and vertical transmission at birth is also reported.
16,17 It is not a zoonosis.
18 The highest concentration of organism was found to be on the surface water of wet rice fields though none of our patients gave any history of recent entry into rice fields or any suspected contaminated area.
18 The clinical presentation is quite variable. It can mimic conditions from acute or chronic forms of infection to various rheumatoid disorders.
14 Patient had initial presentation of chronic granulomatous osteomyelitis due to melioidosis, which remains indistinguishable from tuberculosis or staphylococcal abscess except by microbiological culture.
10,19 One should always consider melioidosis as a differential diagnosis with atypical presentations especially if patient is from endemic area. One patient presented initially with polyarthralgia-like symptom whose serology was similar to typhoid. Later, she presented with multifocal osteomyelitis in leg and foot. Three of them were diabetics. In summary, none had similar presentation, which justifies that musculoskeletal melioidosis can mimic common diseases. In musculoskeletal melioidosis, the diagnosis is usually made by culture from the pus. Blood culture is usually negative. Local pus culture was positive in all cases, while blood culture was positive only in the septicemic case. Even though various indirect hemagglutination tests are reported, we have no experience in using it for diagnosis.
20 Burkholderia pseudomallei are sensitive to ceftazidime, amoxy-clavulanic acid, chloramphenicol, tetracycline and co-trimoxazole.
21,22 Imipenem is also quite effective especially in septicemic type.
23 All our cases were sensitive to these antibiotics. Usually operative intervention along with combination antibiotics (IV ceftazidime and amoxy- clavulanic acid) for 2–3 weeks is instituted instead of a single antibiotic to decrease the chances of recurrence, followed by maintenance oral antibiotic combination therapy of doxycycline, chloramphenicol and co-trimoxazole for 4–6 months. However, we did not use chloramphenicol due to known complication of bone marrow suppression. We used initial combination I.V. antibiotics for three weeks because we felt that this is a slow responsive and difficult condition to treat with known recurrences. It may take about two weeks for fever to subside. Disseminated form may land up in ICUs with increased mortality. We used I.V. ceftazidime and amoxy-clavulanic acid for 2–3 weeks followed by oral therapy with doxycycline and co-trimoxazole for six months. Imipenem is recommended for septicemic form.
Since the organism is resistant to aminoglycosides, macrolides, second generation cephalosporins, rifamycin and fluoroquinolones, hence it is important to start the right antibiotic as any attempt of starting these antibiotics by assumption will certainly lead to failure of therapy.
All our patients had full recovery but for one who died because of disseminated infection, which has high mortality.
2 Till now, there has been no relapse in any of our patients. However, 10% relapse even after 20 weeks of treatment is reported. However, relapse rate increases to 30% if duration of treatment is less than eight weeks.
24 We realize that distribution and frequency of musculoskeletal melioidosis is probably greatly underestimated.
25 It is quite difficult to prevent it in rice producing areas and probably this is why it is more common in southern India. The longer duration of treatment and the cost of antibiotic therapy are important issues. The status of vaccination against infection is poor as repeated natural immunization does not offer any protection. Awareness of this infection, with all its forms of presentation will help early detection, isolation of the organism and disease management.
