Hemophagocytic lymphohistiocytosis due to Burkholderia pseudomallei in a primigravida.

Introduction: Melioidosis is caused by Burkholderia pseudomallei, a gram-negative, saprophytic bacilli, commonly found in soil or contaminated water. As infection with this bacterium produces a wide variety of clinical manifestations the organism is aptly called the “great mimicker”. Even though it is non-fastidious and an easily cultivable organism, it can be misidentified in the automated identification systems. Case report: A 24-year-old primigravida presented with complaints of fever and myalgia of 45 days duration. She was diagnosed to have hemophagocytic lymphohistiocytosis (HLH) based on clinical and laboratory parameters. Blood and bone marrow culture sent to the microbiology laboratory grew non fermenting gram negative bacilli which was misidentified as Burkholderia cepacia by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) technology . It was further identified as B.pseudomalleiby 16S ribosomal RNA sequencing. Patient was commenced on intensive phase therapy with intravenous ceftazidime for 2 weeks, followed by maintenance therapy with oral  trimethoprim and sulfamethoxazole for 3 months. In view of HLH, she was treated with intravenous dexamethasone for 2 weeks which was later switched over to oral dexamethasone for a period of 6 weeks.  She responded well to the treatment, but had to undergo medical termination of pregnancy as there was severe intrauterine growth restriction of the foetus. Conclusion: Prognosis of melioidosis is excellent if early diagnosis and appropriate antibiotic treatment is provided. In this era of automation, it is important to find out if the suspected pathogen is listed in the database of the automated identification system.