A rare case of melioidosis presenting as myositis in Sri Lanka | BMC Infectious Diseases

0

Melioidosis, a multisystem disease with a variety of presentations, was virtually a new disease until recently in the island nation of Sri Lanka. However, in the past decade this has changed with 250 culture positive cases reported. [4]. Most cases have been reported in the western and northwestern provinces and very few in the central highlands. Our patient driver by profession is based in the North West Province which is a hotspot for this emerging disease [4]. A review article on island-wide melioidosis cases describes that 71.6% of all cases were male and many of these were farmers. An interesting fact is that 15% of all males affected were drivers, which can be explained by their constant exposure to dust. [4]. Aerosolized Burkholderia spp. in the dust particles to which drivers in this region are constantly exposed, greatly increase the risk of inoculation and subsequent infection.

Sri Lankan data, similar to international studies, showed that respiratory involvement predominated among cases (28%) [4]. A Sri Lankan study found 20% of cases had musculoskeletal involvement, but it was not mentioned whether they involved only bones, muscles or both. [4]. An Australian study reported that overall soft tissue involvement was minimal; 19 cases out of 540 [2]. Myositis has only been reported once in a hospital less than five kilometers from Kandy National Hospital where this patient was admitted. He describes a patient with myositis affecting the same group of muscles as in our case. However, the patient initially presented with pneumonia and was on treatment [1]. In addition to myositis, our subject had myonecrosis and an intramuscular abscess in the quadriceps. Ours is the only reported case with myositis being the initial presentation of melioidosis and the first to have undergone successful surgical debridement for melioidosis myositis.

Liver and splenic abscesses are a common presentation of the disease, particularly in Thailand, and most have been known to resolve with prolonged antibiotic therapy alone. [2]. Although hepatic functions were disturbed, no evidence of liver abscess was found on imaging in our subject. Acute liver injury could therefore be attributed to sepsis in this case. The rapid normalization of liver functions following medical and surgical management to counter sepsis further confirms this. Neurological manifestations of melioidosis include brain abscess, meningoencephalitis, transverse myelitis, and status epilepticus [4]. Recent animal studies have shown entry of B. pseudomallei from the nasal mucosa via the olfactory nerve to the brain [2]. The single convulsive episode in our patient would most likely have been due to sepsis and/or hepatic encephalopathy secondary to acute liver injury. Another likely cause is meropenem which, although rare, can cause seizures as an adverse effect, especially in older people. However, this is quite unlikely in this patient given the single episode and timing of the attack. Other causes of seizures such as electrolyte imbalances, acid-base disorders, and intracranial injury have been ruled out. However, brain damage without evidence of brain abscess caused by Burkholderia spp. cannot be completely ignored and such presentations may require further investigation, including cerebrospinal fluid (CSF) analysis and MRI.

Diabetes mellitus (DM) has been documented as an important risk factor in acquiring the disease in numerous studies, including “Darwin’s Prospective 20-Year Study of Melioidosis” [2, 5]. According to another study encompassing global data, it was found that up to 60% of people with the disease had diabetes, with type 2 being predominant. [5]. A study involving a mouse model showed the importance of neutrophil function in resistance to melioidosis infection [6]. The neutrophil dysfunction seen in DM therefore weakens immunity and increases the risk of infection, which is reflected in the high percentile of affected individuals being diabetic. In addition to having played a major role in the acquisition of the disease, the DM would have greatly contributed to the sudden escalation of the sepsis observed in the subject due to an immunological dysfunction.

Management of melioidosis includes initial intensive therapy followed by an eradication regimen. Antibiotic options for intensive treatment include ceftazidime, meropenem, and TMP-SMX [5, 7]. Intensive therapy for 10 to 14 days is recommended for isolated skin or lung disease, while for severe deep-seated infections, bone or central nervous system involvement, 4 to 8 weeks of IV therapy may be warranted. [7]. Antibiotic options for eradication include TMP-SMX, doxycycline, chloramphenicol, and co-amoxiclav (as a third-line agent in case of treatment failure or relapse) [7, 8]. Eradication therapy should be continued for 3-6 months depending on clinical and biochemical response (GB, CRP) [7]. According to the antibiotic susceptibility pattern and local microbiology guidelines, the patient was prescribed meropenem IV for 21 days, followed by TMP-SMX and doxycycline as eradication therapy upon discharge. Prolonged intravenous therapy was not recommended even though he had a seizure episode; the reason why could have been multiple rather than infection. In case of post-exposure prophylaxis, current recommendations are TMP-SMX or co-amoxiclav for 21 days while monitoring for any signs of infection. [7]. This was not necessary for the department or laboratory staff in our case. In addition to medical management, ours is a rare case where surgical drainage and debridement was undertaken for melioidosis myositis. In fact, the condition did not improve despite the use of antibiotics until surgical debridement was undertaken, emphasizing the importance of early intervention in the presence of abscess formation and myonecrosis.

Melioidosis can present as primary myositis and should therefore be considered an important differential diagnosis in people with localized muscle pain and soft tissue swelling in endemic areas. Melioidosis myositis can lead to myonecrosis and abscess formation that can lead to rapid disease escalation and sepsis. It is therefore essential to have a high degree of suspicion and to perform early diagnostic imaging followed by early surgery to prevent disease progression and mortality.

Share.

Comments are closed.