ochrobactrum anthropi , formerly classified as achromobacter species or centers for disease control groups vd , is an aerobic , oxidase - producing , non - fermenting , gram - negative bacillus ( 1 ) . o. anthropi is a ubiquitous organism , which is widely distributed in the environment and water sources including normal saline , antiseptic solutions , dialysis liquids , and swimming pools ( 2 ) .
the organism may be part of the normal flora of the large intestine and has been isolated from various clinical specimens ( 3 ) .
o. anthropi is currently considered to be an opportunistic pathogen , and most human diseases reported in the literature are consequences of central venous catheter line infections in severely ill or immunocompromised patients ( 3 , 4 ) .
the pathogen usually displays resistance to commonly used broad - spectrum antimicrobial agents , including penicillins and cephalosporins ( 3 ) .
we report a case of o. anthropi spontaneous bacterial peritonitis in a patient without evident impairment of immune function other than liver cirrhosis .
a review of the literature , found no case of o. anthropi spontaneous bacterial peritonitis up to now .
a 62-yr - old man was admitted to our hospital with a 1-day history of abdominal pain and fever .
his blood pressure was 105/68 mmhg , pulse rate was 105 beats per min , and body temperature was 38.2. abdominal examination revealed diffuse tenderness on the whole abdomen , diminished bowel sound , and splenomegaly .
laboratory tests showed hemoglobin concentration of 12.2 g / dl , leukocyte count of 7,580/l , platelet count of 233,000/l , serum creatinine level of 1.36 mg / dl , serum bilirubin level of 5.0 mg / dl , and serum albumin level of 2.5 g / dl .
the analysis of peritoneal fluid demonstrated an albumin level of 284 mg / dl and leukocyte count of 350/l ( poly 89% , other 5% ) .
empirical treatment with ceftriaxone ( 2 g every 24 hr ) was started with the presumptive diagnosis of spontaneous bacterial peritonitis .
several days later , gram negative bacilli were growing in the cultures of blood and ascites processed by the bactec 9240 unit ( becton dickinson , sparks , md , u.s.a . ) .
the patient 's subsequent hospital course was uneventful except for low - grade fever ( 38 ) . on the 8th day of admission , his blood pressure was 66/40 mmhg , pulse rate was 94 beats per min , and body temperature was 35.2. laboratory tests showed a hemoglobin concentration of 11.0 g / dl , leukocyte count of 13,670/l , platelet count of 232,000/l , creatinine level of 2.26 mg / dl , ascitic albumin level of 470 mg / dl , and ascitic leukocyte count of 1,190/l ( poly 46% , other 50% ) .
we tried to perform an esophagogastroduodenoscopy ( egd ) because of his black and tarry stool , but the patient and his family refused to give his consent to egd . at that time , the gram - negative bacillus was identified as o. anthropi by the gram negative combo 32 kit ( microscan workaway-96 , dade behring , west sacramento , ca , u.s.a . ) , and the biochemical profile determined by the api 20 ne system ( biomerieus , marcy l'etoile , france ) also gave unequivocal identification of o. anthropi .
the organism yielded positive results in tests for urea , ornithine , and esculin hydrolysis and failed to produce hydrogen sulfide in triple - sugar - iron agar , which is collectively consistent with o. anthropi .
the isolate was in vitro susceptible to amikacin , gentamicin , tobramycin , imipenem , meropenem , ciprofloxacin , levofloxacin , and trimethoprim but resistant to all other tested ( -lactam antibiotics including ceftriaxone ) .
the antibiotic was changed to imipenem ( 250 mg every 6 hr , estimated crcl=40 ml / min ) . on the 10th day of admission
o. anthropi is currently considered as an emerging pathogen in immunocompromised patients , especially in the presence of indwelling medical devices .
cytotoxic chemotherapy , recent transplantation , hematologic and non - hematologic malignancies are common underlying conditions ( 5 , 6 ) .
the first case of human infection with o. anthropi , a pancreatic abscess , was reported in 1980 ( 7 ) . since then , most human diseases reported in the literature were a consequence of indwelling medical devices , such as central venous catheter , drainage tubes , and intraperitoneal catheters ( 3 , 4 ) .
the ability of the pathogen to adhere to silicone , similar to that of s. aureus and s. epidermidis , has been shown by in vitro experiment and may play a role in catheter - associated infection ( 6 , 8 , 9 ) .
in addition to central catheter - related infections , o. anthropi may cause localized pyogenic infections ( 10 ) , meningitis ( 11 ) , and osteomyelitis of bone flap following the implantation of contaminated allograft tissue ( 12 ) , endophthalmitis after vitreous and cataract surgery ( 13 , 14 ) , and endocarditis ( 15 , 16 ) .
the pathogen has also been identified as a causative agent of peritonitis in patients undergoing continuous ambulatory peritoneal dialysis ( 17 ) .
the organism is not unusual among infants and toddlers without chronic diseases or other known predisposing factors ( 3 ) .
it has also been recovered from bile , urine , wounds , stool , throat , and vagina .
non - fermenting , gram - negative bacilli that are uncommonly isolated may be quite difficult to identify to the species level .
. further segregation of o. anthropi from other oxidase - positive organisms such as achromobacter , alcaligenes and agrobacterium is based on the production of 3-ketolactose and hydrogen sulfide , growth on cetrimide and hydrolysis of esculin and urea .
accurate identification may require comparison of results obtained by using several identification systems and may sometimes also require comparison of those results of conventional tests such as growth on triple - sugar - iron agar ( 18 ) .
our patient in this report , who had underlying disease of liver cirrhosis as the underlying disease , was suffering from spontaneous bacterial peritonitis caused by o. anthropi .
the patient had not received intravenous injections for more than 6 months , and we could not find any other predisposing conditions .
enteric bacteria could enter the systemic circulation from the portal vein by passage through the liver or by portosystemic shunts in patients with portal hypertension .
enteric bacteria also may gain access to the peritoneal cavity by directly traversing the intact intestinal wall .
this observation highlights that o. anthropi should also be considered a significant pathogen in liver cirrhosis patients .
typically , o. anthropi isolates are susceptible to commonly used aminoglycosides , carbapenems , cotrimoxazole , quinolones , and sulfonamides ; variably susceptible to rifampicin and tetracyclines ; and resistant to beta - lactams ( other than carbapenem ) , chloramphenicol , macrolides , and trimethoprim ( 1 ) .
anthropi infection , there is a poor correlation , however , of in vitro susceptibility data with clinical efficacy of antimicrobial therapy .
treatment failure with imipenem has been reported despite in vitro susceptibility of the strains ( 19 ) . to our knowledge , this case is the first report of spontaneous bacterial peritonitis due to o. anthropi . despite its high level of resistance to antibiotics ,
considering that the majority of cases have been described in debilitated host , o. anthropi has been thought to have low intrinsic pathogenic power and virulence .
however , this case emphasizes that the awareness of the potential role of o. anthropi in causing spontaneous bacterial peritonitis is important , given the serious morbidity associated with disseminated o. anthropi infections .
 we report a case of spontaneous bacterial peritonitis from ochrobactrum anthropi . 
 o. anthropi is recognized as an emerging pathogen in immunocompromised patients . 
 in contrast to most previously described cases , the patient reported here had no indwelling catheter . to our knowledge , 
 no case of o. anthropi spontaneous bacterial peritonitis has been reported in the medical literature until now . 
INTRODUCTION
CASE REPORT
DISCUSSION