Melioidosis

I've already seen such fascinating cases here including multiple cases of melioidosis, which I will likely never encounter again elsewhere. Melioidosis is an infection caused by the gram negative bacterium Burkholderia pseudomallei. Under the microscope it has a safety pin appearance & is motile. It is found in soil & water & is endemic in the NT, especially during the wet season. Patients can become quite ill with acute melioidosis & I've already admitted a few patients with melioid in the less than two weeks I've been in Australia.

My first case of melioid was in a 27-year-old indigenous woman with type 1 diabetes who is from Darwin City & initally presented to the emergency department with complaints of a couple of days of cough with yellow sputum production & severe left sided back & chest pain with coughing. Her blood sugars had been elevated, she was experiencing sweats & chills, decreased appetite, & weight loss. The intial chest x-ray in the ED revealed a large cavitary lung lesion in her left upper lung lobe. Based on these findings, we were highly suspicious for melioid & recommended she be admitted to the hospital for further evaluation. However, like many patients here, she refused to be admitted to the hospital & insisted on leaving. After failing to convince her to stay, we released her on augmentin but after first obtaining blood, urine, & sputum cultures as well as a BPS (Burkholderia pseudomallei screen).

Two days later, her sputum came back with the positive identification for melioid, so we contacted her & convinced her to come into the hospital. We are now treating her with ceftazidime 2g IV every 6 hours as well as bactrim DS 2 tablets every 12 hours. She'll need in the IV antibiotics for at least two weeks & will remain on bactrim for at least another three months. In her case, it is unclear how she was infected with the bacterium. However, diabetes is a known risk factor for melioid.

Today I admitted another another patient with confirmed melioid. This patient is a 57-year-old caucasian man with type 2 diabetes from Gove, which is a small town in the north-west edge of the NT. He works outdoors & remembers scratching his left leg while working sometime in February. Those abrasions have since healed well. However, towards the end of February he also developed elevated blood glucose levels, fevers, chills, rigors, nausea, weight loss, & right flank & back pain. On initial presentation at a local hospital, he was presumed to have a UTI. Cultures were obtained, & he was discharged home on bactrim for his presume UTI.

Despite the bactrim, his symptoms persisted. Subsequently, a gram negative rod organism grew out of his blood cultures so he was admitted to Gove Hospital & started on ceftriaxone & gentamycin. A few days later, melioid was definitively identified & he was switched to ceftazidime & transferred to RDH for further care. He is still having fevers, right flank pain, & abnormal liver function tests, which is concerning for possible liver abscesses, which are a common complication of melioidosis. He will be undergoing a CT of his abdomen & pelvis, which is standard in all patients admitted with melioid given how common it is to develop abscesses. It is unclear how he developed the infection. It may have resulted from the abrasions he sustained sometime in February.

Lastly, I saw a most interesting case today of a 36-year-old indigenous man with no past history who was admitted with four weeks of "flu" like symptoms, fevers, chills, severe right sided abdominal pain, weight loss, cough productive of white sputum, & shortness of breath. On ultrasound & subsequent CT of his abdomen, we discovered multiple large (up to 6cm in diameter) nodules/cysts in his liver. His liver enzymes are also elevated & his coagulation numbers are dramatically deranged with a PTT>200. His BPS is positive & he also has gram negative rods growing from his blood culture, but we are still awaiting final identification. We are treating presumptively for melioid pending the final ID. However, other causes are on the differential including hydatid infection or amoebic infection. As soon as his coagulopathy is corrected, we will obtain a sample from one of the liver lesions. Interestingly, he went fishing in the rain prior to the onset of symptoms & he works as a lawn mower & admits to mowing the lawn barefoot.

Above is a picture of RDH as seen from the "village."