Melioidosis con endocarditis de válvula protésica / Prosthetic valve endocarditis in melioidosis: case report

Resumen La melioidosis es endémica en varias regiones, con predominio en el Sudeste Asiático, norte de Australia, sur de Asia, China y Taiwán. En Sudamérica, Colombia ocupa el segundo lugar de casos de melioidosis, después de Brasil. Su manifestación clínica es variable, desde una infección asintomática hasta un compromiso multiorgánico con formación de abscesos múltiples y choque séptico. El compromiso cardiaco es inusual, con una incidencia menor del 1%. Se presenta el caso de un varón de 51 años, colombiano, con antecedente de una valvula aórtica mecánica, quien presentó un absceso en la pierna derecha y en la válvula cardiaca protésica, aislándose Burkholderia pseudomallei en hemocultivos y en el cultivo de secreción de la pierna. Fue tratado con meropenem y cotrimoxazol, con una adecuada respuesta clínica, requiriendo un reemplazo valvular aórtico.

Abstract Melioidosis is an endemic disease to several regions and occurs predominantly in Southern Asia, Northern Australia, China and Taiwan. In South America, Colombia is second after Brazil in number of melioidosis cases reported. Clinical manifestation varies from asymptomatic infection to multiorgan compromise involving multiple abscesses and septic shock. Cardiac compromise is infrequent, with an incidence of <1%. We report the case of a 51-year-old patient from Colombia with a mechanical aortic valve who had an abscess in right leg and in the prosthetic valve. Burkholderia pseudomallei was isolated in blood cultures and drained pus from the leg cultures. Patient was treated with meropenem and cotrimoxazole and required aortic valve replacement, resulting in adequate improvement in clinical symptoms.

Melioidosis en Colombia, descripción de un caso clínico y consideraciones epidemiológicas / Melioidosis in Colombia, description of a clinical case and epidemiological considerations

Resumen La melioidosis es una enfermedad infecciosa causada por Burkholderia pseudomallei cuyo diagnóstico clínico puede ser difícil debido a su variada presentación clínica y a las dificultades del diagnóstico microbiológico, por lo cual pueden requerirse técnicas moleculares para su adecuada identificación una vez se sospecha su presencia. Son pocos los antibióticos disponibles para el tratamiento de esta enfermedad y, además, deben usarse durante un tiempo prolongado. Aunque se conoce por ser endémica en Tailandia, Malasia, Singapur, Vietnam y Australia, en Colombia se han reportado algunos pocos casos. Se presenta un caso de melioidosis en la región norte de Colombia, se hace una revisión de las características clínicas y el tratamiento, y se describe la epidemiología local de esta enfermedad.

Abstract Melioidosis is an infectious disease caused by Burkholderia pseudomallei whose clinical diagnosis can be difficult due not only to its varied clinical presentation but also to the difficulties in the microbiological diagnosis.Thus, it may be necessary to use molecular techniques for its proper identification once it is suspected. There are few antibiotics available for the treatment of this disease, which must be used over a long period of time. Although it is known to be endemic in Thailand, Malaysia, Singapore, Vietnam, and Australia, in Colombia there are few reported cases. We describe a case of melioidosis in the northern region of Colombia. Additionally, we review its clinical characteristics and treatment and we describe the local epidemiology of this disease.

Melioidosis: A report of two cases.

Melioidosis is increasingly being reported from India in the past few years. Since it can mimic tuberculosis during the initial presentation, treatment with antituberculosis drugs is common. It should be considered in the differential diagnosis of any pyrexia of unknown origin. We report two cases of melioidosis that presented with pyrexia of unknown origin and a localized cutaneous abscess over the chest wall.

False-positive widal in melioidosis.

Enteric fever is endemic in this part of the world, and Widal test is one of the time-honored laboratory tests that are being used for years to diagnose the disease. On the other hand, melioidosis is a newly emerging disease from this region, which is most often misdiagnosed or underdiagnosed by clinicians. It is well accepted that false-positive Widal reactions following certain non-typhoid Salmonella infections may occur commonly. Three cases of high titers of Widal test are described, where melioidosis was the actual diagnosis in every occasion and was never suspected until diagnosed microbiologically. All the patients had shown a partial response to ceftriaxone. Blood and pus cultures grew Burkholderia pseudomallei, whereas Salmonella typhi was not isolated from blood in any patient. With appropriate antibiotics, the patients showed clinical and microbiological improvement with lowering of Widal titers. These 3 cases show that high Widal titer in any patient may mislead the diagnosis of melioidosis, and further laboratory workup should always be done to rule out melioidosis, especially in cases with nonresponsiveness to treatment.

Isolated liver abscesses in melioidosis.

Melioidosis is a suppurative chronic infection caused by a gramnegative bacterium, Burkholderia pseudomallei. We report two patients who presented with isolated liver abscesses caused by this pathogen. Both patients presented with high-grade fever and abdominal pain. On examination they were toxic and had tender hepatomegaly. Investigations showed leucocytosis and a shift to the left. Early diagnosis of melioidosis was made by culture and growth of Burkholderia pseudomallei from aspirated pus from the abscesses and the patients were treated with ceftazidime and co-trimoxazole. Despite institution of antibiotics both the patients succumbed to their illness. Melioidosis is an emerging infection in the Indian subcontinent and can cause isolated liver abscesses.

Clinical guideline for diagnosis and management of melioidosis

Melioidose é uma infecção emergente no Brasil e em países vizinhos da América do Sul. O amplo espectro de apresentação clínica inclui pneumonia adquirida na comunidade, septicemia, infecção do sistema nervoso central e infecção de partes moles de menor severidade. O diagnóstico depende essencialmente da identificação microbiológica. Burkholderia pseudomallei, a causa bacteriana da melioidose, é facilmente cultivada em sangue, escarro e em outras amostras clínicas. Entretanto, B. pseudomallei pode ser difícil de identificar com segurança e também ser confundido com outras bactérias Gram negativas. Os exames sorológicos podem dar suporte a um diagnóstico de melioidose, mas não fornece um diagnóstico definitivo por si só. A realização de investigação laboratorial seqüenciada pode ajudar a reduzir o risco de não reconhecer isolados incomuns de B. pseudomallei. O tratamento antibiótico recomendado para infecção severa é Ceftazidima ou Meropenem endovenosos por várias semanas, seguido por um tratamento oral com uma combinação de Sulfametoxazol-Trimetopim e Doxiciclina por até 20 semanas. O uso consistente do diagnóstico microbiológico e o tratamento rigoroso da infecção severa com antibióticos adequados nas duas etapas, aguda e de erradicação, contribuirão para a redução da mortalidade por melioidose.

The effect of methanolic extract of Tamarindus indica Linn. on the growth of clinical isolates of Burkholderia pseudomallei.

Burkholderia pseudomallei (Pseudomonas pseudomallei) causes melioidosis, a life-threatening infection common among paddy cultivators in Southeast Asian countries. No plant materials have been investigated for its activity against B. pseudomallei. Therefore, a preliminary study was carried out using disc diffusion and minimum inhibitory concentration (MIC) methods to evaluate the anti-B. pseudomallei activity of five Indian medicinal plants documented to have been used for several ailments in the ancient Indian scriptures. The leaf extracts of Tamarindus indica, Lawsonia inermis, and Hibiscus rosa-sinensis, the rhizome extracts of Curcuma longa and the seeds of Vigna radiata were prepared using methanol as solvent. The disc diffusion and MIC methods were used to assess the anti-B. pseudomallei activity of the plants tested. Only methanol leaf extracts of Tamarindus indica exhibited anti-B. pseudomallei activity starting from disc concentrations of 150 mug by the disc diffusion method. The other plants failed to show any zone of inhibition. MIC assay revealed that the MIC and minimum bactericidal concentration (MBC) for B. pseudomallei were 125 mug/ml. Our preliminary finding showed that methanolic extracts of Tamarindus indica has anti-B. pseudomallei inhibitory potentials under in vitro conditions. Extensive animal studies may be required before investigating the role of Tamarindus indica for treating melioidosis.

Fatal septicemic melioidosis in young adult

Melioidosis caused by B. pseudomallei remains dormant for months, years and even decades but becomes active when host is immunocompromised by drugs or disease including diabetes mellitus. Patients with diabetes mellitus shows a severe serious presentation of melioidosis. This is a case report of a 26 year old man with diabetes mellitus presented with fever, shortness of breath, left loin pain, dysuria and haematuria. The outcome of this melioidosis case and differential diagnosis are discussed

Severe community-acquired pneumonia and sepsis caused by Burkholderia pseudomallei associated with flooding in Puerto Rico

Burkholderia pseudomallei (melioidosis) is usually found in endemic areas of Southeast Asia and Northern Australia. However, a few cases of confirmed melioidosis indigenous to Puerto Rico and the Americas have been reported previously. We describe the occurrence of a B. pseudomallei infection in a female with insulin-dependent diabetes mellitus exposed to flood waters in Puerto Rico. We conclude that B. pseudomallei should be considered a potential pathogen in high-risk patients with severe community-acquired pneumonia and sepsis in Puerto Rico especially in individuals exposed to flood waters during rainy seasons. A more thorough epidemiologic and microbiologic surveillance with environmental sampling may be warranted in the island

Melioidosis en Costa Rica: reporte del primer caso / Melioidosis in Costa Rica: report first case

Melioidosis es una enfermedad infecciosa causada por la Burkholderia pseudomallei. Esta enfermedad es endémica en áreas tropicales de Asia y Australia y ha habido reportes aislados en Centro y Sur América. Aquí nosotros informamos del primer caso probado de melioidosis en Costa Rica, correspondiendo a un paciente sin historia de viajes a lugares endémicos. El paciente consultó por una bronconeumonía de adquisición comunitaria y sepsis. El hecho que al aislamiento bacteriano sea tan inusual en nuestro país implicó un retraso subsecuente en el inicio del tratamiento antibiótico específico en este caso, lo cual pudo influir en la evolución tan tórpida del paciente. Esto nos plantea el interrogante de si esta enfermedad debe ser incluida en el diagnóstico diferencial de sepsis de adquisición comunitaria en nuestro país

Comparison between the antimicrobial susceptibility of Burkholderia pseudomallei to trimethoprim-sulfamethoxazole by standard disk diffusion method and by minimal inhibitory concentration determination.

Melioidosis, an infection caused by Burkholderia pseudomallei, usually occurs in immunocompromised patients and requires prolonged antibiotic therapy. Previously, oral trimethoprim-sulfamethoxazole (TM/SM), an inexpensive and effective drug has been used as a maintenance therapy. The susceptibility of B. pseudomallei to TM/SM by the standard disk diffusion method is very low. However, some patients who were treated with TM/SM as a maintenance therapy despite the in vitro resistance showed good clinical responses. There were no data comparing the susceptibility of B. pseudomallei by the standard disk diffusion method with other quantitative susceptibility tests. The objective of this study was to determine the agreement between the antimicrobial susceptibility of B. pseudomallei to TM/SM by standard disk diffusion and minimal inhibitory concentration determination (MIC). We performed the susceptibility test of 144 strains of B. pseudomallei to TM/SM by both the standard disk diffusion and microbroth dilution MIC. The sensitivity results were 53.5 per cent and 84.0 per cent respectively. The agreement between the 2 tests was very poor (Kappa = 0.14; 95% CI = -0.01 to 0.29). The false resistant rate by the standard disk diffusion test was 67.9 per cent. Further in vitro susceptibility and clinical study are needed to define the interpretive criteria that correlate with clinical response.

Burkholderia pseudomallei: the unbeatable foe?

Although melioidosis has been recognized in Thailand for many years and considerable progress in term of diagnosis and treatment was achieved, B. pseudomallei is still "the unbeatable foe", for several reasons as outlined here: under-recognition, high case-fatality rate, unacceptable relapse rate and a "time-bomb" for sero-positive patients. Melioidosis is largely restricted to certain geographical areas. In Thailand, it had long been considered a rare disease in Thailand until ten cases with culture-proven melioidosis were reported by Sompone Punyagupta and his associates at a meeting of the Infectious Disease Group of Thailand. Since then awareness of young physicians and laboratory personnel for melioidosis has been increased. The most dramatic consequence was seen at Sappasitprasong Hospital in Ubon Ratchathani where over 100 strains of B. pseudomallei are isolated each year. But the frequent isolation of B. pseudomallei is surprisingly restricted to some provinces in the northeast, namely Khon Kaen and Ubon Ratchathani provinces and only 1-10 cases or none from adjacent provinces. The discrepancy was well illustrated by mapping the number of isolations by province. Thus many cases of septicemic melioidosis are certain to receive inappropriate chemotherapy and nearly half of them probably leave this world without proper diagnosis in area where under-recognition unfortunately still prevails. Mortality in disseminated septicemic melioidosis used to occur in 82-87% of the patients who were treated with doxycycline, chloramphenicol, cotrimoxazole and kanamycin and in non-disseminated septicemic melioidosis about 20%. With ceftazidime therapy, the mortality rate was cut by half to 35-40%. About 50% of the patients deteriorated rapidly and died within the first few days of fever. Fatalities are related to the speed of positive results of blood culture. Accordingly, awareness of the disease, familiarity of clinical syndrome compatible with septicemic melioidosis, gram-staining of exudate to include or exclude melioidosis, are all crucial factors to lead to proper empiric chemotherapy. Since the addition of anti-cytokine and platelet activating factor receptor antagonist to current antimicrobials failed to lower the mortality rate, we need to find a new antimicrobial such as protegrin-1 which exhibits rapid microbicidal activity, especially against stationary-phase cell. We need to optimize the bactericidal action of currently used antimicrobials by examining their pharmacokinetics. With prolonged maintenance treatment with cotrimoxazole plus doxycycline or co-amoxiclav, relapse occurs in 4 to 23%. Various explanations for the relapse are the ability of the organism to produce glycocalyx, form microcolonies in damaged tissues and survive within phagocytic cells. Again, the bactericidal antimicrobial which is concentration-dependent, may be used to shorten the duration of treatment and reduce relapse. Studies so far can not relate relapse to any defect of host defense mechanism. In endemic areas, seroepidemiological surveys showed that infection, mostly latent, occurred fairly commonly since childhood as 80% of children had antibodies by the age of four years. However, clinical melioidosis is more common in the elderly which in some cases are due to reactivation of primary latent infection. Since the incubation period of the reactivation can vary from weeks to many years, a vaccine or short-course secondary chemoprophylaxis may be possible interventions for the high risk group to get rid of the "time-bomb" reactivation. The vaccine may also be used to reduce the relapse rate. We need to discover the cellular determinants which is critical to awake the host defense to the sleeping bacteria and provoke local inflammatory response to newly born bacteria before dissemination takes place again. Basic research into the pathogenic mechanisms are key to understanding how to make an effective vaccine.

Cefoperazone/sulbactam + co-trimoxazole vs ceftazidime + co-trimoxazole in the treatment of severe melioidosis: a randomized, double-blind, controlled study.

A prospective randomized, double-blind, controlled study of cefoperazone/sulbactam (cefoperazone 25 mg/kg/day) + co-trimoxazole (trimethoprim 8 mg/kg/day) vs ceftazidime (100 mg/kg/day) + co-trimoxazole (trimethoprim 8 mg/kg/day) in the treatment of severe melioidosis was conducted at Srinagarind Hospital, Khon Kaen University, Khon Kaen, Thailand, from July 1995 to September 1996. A total of 84 patients were enrolled in the study. Forty of them (48%) had culture-proven melioidosis and were randomly assigned to one of the two treatment groups, each group with 20 patients. Two cases (one in each treatment group) were excluded from the final analysis due to incomplete data. There was no significant difference in the mortality rate between the two groups-16 per cent (3/19) in the cefoperazone/sulbactam group vs 21 per cent (4/19) in the ceftazidime group (p > 0.05). Bacteriological responses of successfully treated patients were similar in both groups, and both treatment regimens were well tolerated. Cefoperazone/sulbactam + co-trimoxazole can therefore be used as an alternative treatment for severe melioidosis. However, to further support this conclusion, a study with a larger patient population is needed.

Cerebral abscesses due to Pseudomonas pseudomallei.

Two cases of cerebral abscesses caused by Pseudomonas pseudomallei are reported. The first case, a 51-year-old women had a sudden onset of progressive right hemiparesis and right facial palsy and died within 7 days. Postmortem examination disclosed brain abscess in association with disseminated infection outside the central nervous system. The second case, a 9-year-old boy displayed cerebral abscesses as an isolated manifestation. Recovery occurred after treatment with ceftazidime. Review of the ten case reports of cerebral melioidosis revealed that the lesion occurred in patients of all ages and was more common in men than in women. The frontoparietal lobe was the most common location. Fever, headache, and hemiparesis were frequent clinical manifestations while seizures, ataxia were uncommon. CT scanning, serum antibody titer along with hemoculture were useful investigate tools. The importance of early diagnosis and prompt treatment is emphasized for this fatal but treatable disease.