Community-Acquired urinary tract infection by pseudomonas oryzihabitans.

Pseudomonas oryzihabitans and Chrysomonas luteola has been placed in CDC group Ve2 and Ve1 respectively. These bacteria appear to be emerging pathogens. P. oryzihabitans was isolated from cases of bacteremia, CNS infections, wound infections, peritonitis, sinusitis, catheter associated infections in AIDS patient, and pneumonia. Most of the reports of P. oryzihabitans infection were of nosocomial origin in individuals with some predisposing factors. We report here a case of community acquired UTI by P. oryzihabitans in an immune-competent patient with stricture of urethra.

INTRODUCTION

Pseudomonas oryzihabitans, previously known as Flavimonas oryzihabitans has been placed in CDC (CDC: Centers for Disease Control) group Ve-2. P. oryzihabitans has been recovered from various clinical samples, including wound swab, sputum, ear swab, conjunctival scrapings, urine, peritoneal fluid, and blood. P. (Flavimonas) oryzihabitans bacteremia was also reported in a neonate.[12]

P. oryzihabitans appears to be an emerging pathogen. P. oryzihabitans is an uncommon pathogen associated with indwelling intravenous catheter infection.[34] We report a case of urinary tract infection (UTI) caused by P. oryzihabitans in a patient with anterior stricture of urethra. Chrysomonasluteola belongs to CDC group Ve-1 Recently, two cases of infection from Indian patients by Chrysomonas have been reported, from Mumbai and Hyderabad.[56] There is no documented report of P. oryzihabitans infection in any Indian patient. In May 2011, six cases of P. oryzihabitans bacteremia in neonatal intensive care unit were reported.[2]

CASE REPORT

A 45-year-old male patient was admitted in the surgery ward with complaints of difficulty in passing urine since two months. There was no history of burning micturition and hematuria and no history of chronic illness suggestive of immunocompromised status. Test for HIV and hepatitis B surface antigen (HBsAg) was negative. Hemoglobin was 13.8g/dL and erythrocyte sedimentation rate (ESR) was19 mm/h. General and systemic examination was normal. Ultrasonography of the abdomen and pelvis was normal. Retrourethrogram showed narrowing in the anterior urethra. The case was provisionally diagnosed as stricture of urethra with UTI. Urine sample was received for culture and sensitivity, and processed by routine semiquantitative method. On blood agar and Muller Hinton agar rough wrinkled yellow pigmented colonies were grown [Figure 1] and on MacConkey agar, nonlactose-fermenting colonies were grown. Gram-negative, motile, oxidase-negative, nonfermenter bacilli were isolated. The isolate was further identified as P. oryzihabitans (% id98.3) by the API ID 32 GN automated identification system (bioMérieux, Marcy I’ Étoile, France). Identification was based on the following tests: Negative nitrate reduction, esculin hydrolysis, lysine decarboxylase, arginine dehydrolase, and orthonitrophenyl-β-D-galactopyranoside activity (ONPG), positive oxidation fermentation glucose, maltose, mannitol, and xylose activity. Antibiotic sensitivity was done by disc diffusion method using Clinical and Laboratory Standards Institute (CLSI) guidelines. The isolate was sensitive to piperacillin, cephalosporins, imipenem, meropenem, cotrimoxazole, aminoglycosides, and fluoroquinolones, and resistant to nitrofurantoin. The patient was treated with oral norfloxacin 400 mg twice daily for ten days, and advised to come for follow-up after 15 days. Initial retrourethrogram showed narrowing in anterior urethra, but as the patient responded to antibiotic treatment and dysuria was relieved, repeat retrourethrogram was not done.

Figure 1

Colonies of P. oryzihabitans on Muller Hinton agar (×100)

DISCUSSION

In hospitals, P. oryzihabitans has been isolated from sink drains and respiratory therapy equipment. In nature, this organism has been isolated from rice paddy. P. oryzihabitans bacteremia was reported in 12 patients at the National Taiwan University hospital.[4] Four cases of community-acquired pneumonia infection by P. oryzihabitans were reported, three in HIV-positive patients and one in a patient with chronic myeloid leukemia.[7] Most of the reports of P. oryzihabitans infection were of nosocomial origin in individuals with one of the predisposing factors like low-birth-weight neonate, premature neonate, biliary tract infection, peritonitis, subdural empyema, or pneumonia, and were associated with the presence of indwelling catheters.[1248] There are very few reports of community-acquired infection by P. oryzihabitans, like the infection of a Hickman catheter traced to a synthetic bath sponge, pneumonia, or a soft tissue infection.[379] Some case reports also have been documented in otherwise previously healthy individuals.[10] P. oryzihabitans isolated from the blood sample of catheter associated infection in the AIDS patient was sensitive to broad-spectrum cephalosporins, aztreonam, imipenem, aminoglycosides, ciprofloxacin, and trimethoprim-sulfamethoxazole, and resistant to ampicillin, amoxycillin-clavulinic acid and cefazolin.[3] In contrast to the previously reported cases, where Pseudomonas (Flavimonas) showed resistance to cefazolin, cefuroxime, and trimethoprim, our isolate was found to be sensitive to these antibiotics[8] This suggests that the strain could well have been a community isolate.

Although P. oryzihabitans has been isolated occasionally from the environment, the source of human infection has been well documented only in a few cases; in two reports, the source of infection was traced to a bath sponge.[23] A PubMed search for P. oryzihabitans infection in Indian patients did not yield any result. This may be the first case report of P. oryzihabitans UTI infection in an Indian patient.

CONCLUSION

Although a saprophyte, P. oryzihabitans could well emerge as a potential pathogen. Therefore, clinical microbiologists should not ignore them as laboratory contaminants, because reports of infections are on the rise both in immune-compromised and in immune-competent individuals. Thus, proper identification of the nonfermentor is the need of the day. Clinicians and laboratory personnel also have to be made aware of the pathogenic role of P. oryzihabitans which may become increasingly prevalent in the near future.