Melioidosis is reported to cause a high fatality rate in children, even in the absence of risk factors for disease. The aim of this study was to identify characteristics of fatal pediatric melioidosis infection. We performed a retrospective analysis of children aged < 15 years with culture-confirmed melioidosis admitted to Bintulu Hospital in Sarawak, Malaysian Borneo, from January 2011 to December 2020. Forty-one children had culture-confirmed melioidosis. Nine (22%) had a fatal outcome; 8 (89%) had no predisposing risk factors. Bacteremia, septic shock, and acute respiratory distress syndrome were present in all fatalities. Demographic characteristics, presenting manifestation, and disseminated infection were not significantly associated with mortality, whereas the presence of splenomegaly, cytopenia, disseminated intravascular coagulation, and hepatobiliary dysfunction, all of which are features of hyperferritinemic sepsis-induced multiple-organ dysfunction syndrome, were associated with mortality. Hyperferritinemic sepsis-induced multiple-organ dysfunction syndrome may be a key component in the pathogenesis of fatal pediatric melioidosis.
A 35 year old diabetic presented with features of septicaemia and developed cardiac tamponade. He was found to have pulmonary, acute septicaemic and pericardial melioidosis. Some initial improvement was achieved with medical therapy but only with surgical intervention was a successful outcome achieved.
OBJECTIVES: The bsa locus of Burkholderia pseudomallei encodes several proteins that are components of the type III secretion system (TTSS). BipC was postulated as one of the TTSS-3 effector proteins, but its role in the pathogenesis of B. pseudomallei infection is not well understood. Thus, the aim of this study was to determine its role(s) in the virulence of B. pseudomallei pathogenesis.
METHODS: A bipC TTSS-3-deficient strain of B. pseudomallei and complemented strains were generated to assess the role of BipC as a type III translocation apparatus. Human cell lines and a mouse model of melioidosis were used for in vitro and in vivo assays, respectively.
RESULTS: A significant 2-fold reduction was demonstrated in the percentage of adherence, invasion, intracellular survival, and phagosomal escape of the bipC mutant. Interestingly, microscopic studies have shown that BipC was capable of delayed B. pseudomallei actin-based motility. The virulence of the mutant strain in a murine model of melioidosis demonstrated that the bipC mutant was less virulent, compared with the wild type.
CONCLUSION: The results suggested that BipC possesses virulence determinants that play significant roles in host cell invasion and immune evasion.
KEYWORDS: BipC; Burkholderia pseudomallei; host cell invasion; type III secretion system; type III translocation apparatus; virulence
Pseudomonas pseudomallei, a gram negative organism causing melioidosis, is found in tropical and subtropical regions. It may manifest as a pulmonary lesion, osteomyelitis, soft tissue abscesses, abscesses in various organs or in septicaemic form. Melioidosis of the parapharyngeal space has not been reported so far. A case of melioidosis of the parapharyngeal space which was successfully treated by drainage and prolonged antibiotic therapy is reported here. Melioidosis should be suspected in severe forms of deep neck space infection, especially if the patient comes from an endemic area.
Klebsiella ozaenae is a Gram negative bacillus. It has been described as a colonizer of oral and nasopharyngeal mucosa and is a cause of atrophic rhinitis. Klebsiella ozaenae has seldom been isolated from serious infections. However, several reports have stated that Klebsiella ozaenae may cause invasive infections and even mortality. We report a 55-year-old man with Klebsiella ozaenae infection causing abscesses involving the right eye and left kidney and possibly also in the brain, lungs and prostate. The isolates were sensitive to ceftazidime, ciprofloxacin, chloramphenicol, gentamicin and sulfamethoxazole-trimethoprim but resistant to ampicillin. He responded well to 4 weeks of i.v. ceftazidime and i.v. amoxycillin-clavulanic acid. To our knowledge, such a multiorgan infection has not been reported previously for this organism.
B. pseudomallei has been shown to persist intracellularly in melioidosis patients until reactivated by decreasing immunocompetence. We have shown by transmission electron microscopy the internalization of B. pseudomallei by human macrophages via conventional phagocytosis enclosed within membrane-bound vacuoles or phagosomes. Ferritin labeled lysosomes provided evidence of phagosome-lysosome fusion. Ingested bacilli were designated as "intact" or "damaged" on the basis of their ultrastructural features. An intact bacterium was seen with low electron opaque central nuclear region surrounded by dense bacterial cytoplasm, bounded externally by bacterial plasma membrane and cell wall. In contrast, B. pseudomallei were considered damaged when seen with cavitation within the central nuclear region, separation of bacterial cytoplasm from the cell wall, herniation of cytoplasmic contents and lamination of bacterial cell wall and its surrounding electron transparent zone. Our observations indicate that the microbicidal mechanism(s) in B. pseudomallei-infected macrophages failed to ensure complete clearance of the organism and this failure probably facilitates intracellular persistence and proliferation, and this may be one of the survival strategies adopted by this organism.
This report is of a man who suffered from chronic melioidosis contracted in Malaysia. In the course of the disease he had a lobe of a lung resected, developed empyema and, while this was still draining, developed infection in an ankle. Both the empyema thoracis and the ankle infection were due to Pseudomonas pseudomallel. He now appears to be cured, probably by massive doses of tetracycline.
We report a case of melioidosis presenting as peritonitis in a patient on continuous ambulatory peritoneal dialysis (CAPD). A 47-year-old man, a lorry driver, with end-stage renal disease due to diabetes mellitus on CAPD presented in PD-related peritonitis. He was started on intraperitoneal cloxacillin and ceftazidime, and changed to intraperitoneal vancomycin and meropenam after day 5 due to nonresponse. Burkholderia pseudomallei was identified from the dialysate culture. He was treated with intraperitoneal meropenam for two weeks, and IV ceftazidime for 4 weeks. He responded, and the Tenckhoff catheter was not removed. He was discharged well and continued on oral sulfamethoxazole/trimethoprim for six months. This patient had done his PD exchanges in a lorry.
We analyzed the epidemiological data of all people who were involved in the search and rescue operation in Lubuk Yu, a natural recreational forest with waterfall and stream. The hospital admission records of the cases who fulfilled the case definition and the environmental samples result taken at Lubuk Yu recreational area were studied. 153 people were exposed to this outbreak, 85 (55.5%) were professional rescuers from various government agencies and 68 (44.5%) were villagers. 21 fulfilled the case definition. Ten cases were confirmed melioidosis, six melioidosis alone and four coinfected with leptospirosis. There were eight deaths in this outbreak, seven were villagers and one professional rescuer. Overall case fatality was 70%. All confirmed melioidosis cases and seven who died had diabetes mellitus. The morbidity rate were higher among the villagers, 23.5% compared to professional rescuers, 5.9%. The case fatality rate were also higher in this group which was 100% compared to 33.3% in professional rescuers. The soil and water samples in Lubuk Yu recreational area were positive for leptospira and Burkholderia pseudomallei. The presence of co-infection and co-morbidities especially diabetes mellitus among the exposed led to the high mortality in this outbreak hence a high index of suspicion is important among the healthcare professionals in the management of melioidosis cases. To avoid similar incident in future, search and rescue operation should be only conducted by professional rescuers with appropriate personal protective equipment. A register of rescuers should be maintained for surveillance and follow up if necessary.
Melioidosis is an infection caused by Gram negative bacterium Burkholderia pseudomallei leading to abscesses in lungs, liver, spleen, musculoskeletal system, prostate and sepsis. We present a rare case of purulent pericardial effusion caused by melioidosis with concomitant pneumonia and splenic abscesses. The patient underwent pericardiocentesis and successfully recovered from cardiogenic and septic shock.
Melioidosis has a high annual incidence and mortality rate in Pahang, Malaysia. We initiated the first melioidosis registry in the country on 1st July 2005 to improve the management of melioidosis in the state. Continuous medical education on melioidosis was carried out in all hospitals in the state to highlight the magnitude of the disease and to educate the doctors on the treatment of the disease. All culture confirmed cases were registered and analysed. During the one-year study period from 1st July 2005 till 30th June 2006, a total of 63 patients had positive culture for Burkholderia pseudomallei. The calculated annual incidence of melioidosis in Pahang state was 4.3 per 100,000 population per year (Adult, 6.0 per 100, 000 population per year and paediatric, 1.6 per 100,000 population per year). There were 55 Malays (87.3%), three Chinese (4.8%), four aborigines (6.3%) and one Indonesian. Nine (14.3%) were less than 18 years old. The median age was 49 years (range: 1-68 years). Only one patient (1.6%) had a previous history of confirmed melioidosis. With this programme, we had observed a decline in adult mortality from 54% to 44%, although this was not statistically significant. However, culture-confirmed relapses had dropped from 19% to nil. Several measures need to be taken to decrease mortality from melioidosis in endemic countries.
We conducted a retrospective review of 135 patients with melioidosis in Pahang from January 2000 to June 2003. Patients were mostly male (78.5%) and Malay (83%) with a median age of 51 years. Seventy four percent of patients were diabetic. Common presentations were pneumonia (40.7%), septicaemic without obvious source of infection (19.3%) and multiple organ involvement (15.6%). Only 32.7% were given appropriate antibiotics empirically. The overall mortality was 54% with most deaths (65%) occurring within 48 hours of admission. Patients with pneumonia, multiple organ involvement and septicaemic of unknown source had higher mortality as compared to patients with subcutaneous, musculoskeletal or single internal organ involvement without pneumonia (p < 0.001). The relapse rate was 19.2%.
A 5 year retrospective review of cases of melioidosis was carried out in Sultanah Aminah Hospital, Johor Bahru. There were 44 new cases of melioidosis which was proven by either blood or pus culture growing Burkholderia pseudomallei from the period between January 1999 and December 2003. Of these, 38 (86.4%) were males compared to only 6 (13.6%) females. Thirty-one (70.5%) were Malays, 7 (15.9%) were Chinese, 5 (11.4%) were Indians and 1 (2.2%) was a Sarawakian. The peak age group was between 50 and 59 years (31.8%). Out of these 44 new cases, only 32 medical records could be retrieved and analysed. Twenty-four out of 32 patients (75%) analysed had diabetes mellitus, 4 had chronic or end stage renal failure (CRF/ESRF) and only 1 had Human Immunodeficiency Virus (HIV). One case of "near drowning" was also recorded. Twenty-one out of 44 patients or 47.7% died, of which 8 (38.1%) died within 24 hours of admission. Pulmonary involvement was recorded in 62.6% of the patients but many had signs and symptoms of multiorgan involvement.