malakoplakia is a rare chronic inflammatory disease that occurs most commonly in the genitourinary tract , especially the urinary bladder . most patients have associated conditions characterized by some degree of immunosuppression , as seen in solid - organ transplants , autoimmune diseases requiring steroid use , chemotherapy , chronic systemic diseases , alcohol abuse and poorly controlled diabetes.1 ) despite some characteristic histological features including the presence of large histiocytes with clusters of michaelis - gutmann ( mg ) bodies , malakoplakia of the kidney is difficult to diagnose because of its rarity and varying histological pictures.2 ) to our knowledge , there have been no case reports of malakoplakia of the kidney in a secondary adrenal insufficiency from korea . here , we report an unusual case of renal malakoplakia involving the perirenal space and extending to the descending colon in a 65-year - old korean woman with secondary adrenal insufficiency and diabetes mellitus . in march 2010 , a 65-year - old woman was transferred from the national police hospital ( nph ) to our facility , shinchon severance hospital ( seoul , korea ) via the emergency room ( er ) , presenting with a decreased level of consciousness . according to her medical history , she had hypertension , diabetes mellitus for 10 years , recurrent cystitis , and degenerative arthritis . she had been taking dexamethasone ( 5 mg , once a day ) for the degenerative arthritis for approximately five years up to the time of admission . three weeks before the admission , she had been hospitalized at nph due to drowsy mentality for 3 or 4 hours . on the day of admission at nph , she presented with a fever ( 38.8 ) and dyspnea . the patient was given antibiotics ( ceftriaxone and azithromycin ) for 14 days , on suspicion of community - acquired pneumonia . thereafter , her presenting symptoms were improved , but she complained of consistent pain in the left lower quadrant of the abdomen . abdomen - pelvis computed tomography ( ct ) scan was performed , which showed the mass - like lesion in the left renal area suspecting abscess . while being treated with ciprofloxacin , she developed a decreased level of consciousness . upon physical examination on the day of the admission to our hospital , her initial vital signs were as follows : blood pressure 134/71 mm hg , pulse rate 95 bits per minute , body temperature 36.4 , and respiration rate 18 breaths per minute . her breathing sound was clear , and her heart sound was normal without any murmurs . laboratory studies had the following results ( reference values ) : low sodium ( na ) levels of 112 mmol / l ( 135.0 - 145.0 ) , potassium ( k ) 3.4 mmol / l ( 3.5 - 5.5 ) , chloride ( cl ) 77.0 mmol / l ( 98 - 110 ) , total co2 21.0 mmol / l ( 24 - 30 ) , low serum osmolality 240.0 mosm ( 289.0 - 308.0 ) , and normal urine osmolality 315.0 ( 50.0 - 1200 ) . initial urinalysis results showed 3 - 5 white blood cells / high - power field and yeast - like organisms . in the radiological examination , there was no acute ischemic lesion in the brain magnetic re sonance imaging and angiography with neck angiography ( 3d ) , and no specific finding on the chest x - ray . sodium replacement therapy for hypotonic euvolemic hyponatremia had been started from the day of admission . at that stage , secondary adrenal insufficiency due to exogenous steroid was suspected . a low dose adrenocorticotropic hormone ( 1 g cosynthropin ) stimulation test was conducted to diagnose the secondary adrenal insufficiency . the stimulation test showed that there was adrenal insufficiency ; basal level of cortisol 8.56 g / dl , peak level during the hour - long test 13.94 g / dl ( table 2 ) . steroid hormone ( hydrocortisone sodium succinate ; solucortef ) was replaced . on the third day after admission , her general condition including clear consciousness was improved , with a normal level of serum sodium ( 136 mmol / l ) , and her steroid hormone dosage had been gradually tapered down and was maintained at 7.5 mg ( 5 mg , 2.5 mg two times a day ) of prednisolone acetate . however , the patient complained of myalgia , which was accompanied with leukocytosis ( white blood cell count 13,650 g / l [ neutrophil 84.9 % ] ) . radiological reading of the abdomen - pelvic ct conducted on the second day after admission showed that there was an ill - defined inflammatory lesion with multifocal abscess pockets in the left perirenal space , which was suspected of actinomycosis of the descending colon , extended to the left kidney ( figure 1a ) . compared to the abdomen - pelvic ct finding performed outside , the lesion seemed to have decreased slightly in size . urinalysis was repeated and showed many white blood cells per high - power field and yeast - like organisms , which was confirmed as yeast in the urine culture . considering the laboratory and radiologic findings , intravenous antibiotic treatment was started ( ubacillin 1,500 mg a day ) for suspected actinomycosis . no specific lesion was found at the colonoscopy performed to confirm the diagnosis of actinomycosis . on the 12th day after admission the histology of the lesion showed a collection of foamy histiocytes also known as von hansemann cells with von - kossa stain positive spheres ( michelis - gutmann body ) ( figure 2 ) . the patient presented dysuria and urgency , and antibiotic treatment was changed to oral ciprofloxacin ( 500 mg a day ) . on the 15th day after admission , she was discharged , as her presenting symptoms and laboratory findings were improved . about 4 months after discharge , the patient was readmitted presenting with general weakness for one month . the findings of the abdomen - pelvic ct conducted upon readmission ( figure 1b ) showed that the extent of the malakoplakia in the perirenal space had decreased since 9 week prior , as she had been taking the oral antibiotics . she has had follow - up in our outpatient clinic ever since , taking oral trimethoprim - sulfamethoxazole . malakoplakia is an uncommon but distinctive type of chronic granulomatous inflammation . upon microscopic examination , malakoplakia is characterized by the presence of sheets of histiocytes with granular cytoplasm ( von hansemann cells ) and the formation of intracellular bacterial inclusions called michaelis - gutmann bodies.3 - 7 ) the pathogenesis is poorly understood , but it is thought to result from acquired bactericidal defects in macrophages occurring mostly in patients with chronic debility or immunosuppression , a kidney transplant requiring steroids , or azathioprine.8,9 ) these observations suggest that an altered immune response may play a role in the pathogenesis of the disease . individuals with diabetes mellitus have a greater frequency and severity of infection . from the earliest reports on studies of adrenocortical function , there has been impressive evidence that adrenocortical hormone , and more specifically cortisol , is essential for normal immunity . otherwise , prednisone , triamcinolone , dexamethasone and similar commercially popular steroids have the dangerous side - effect of lowering resistance to infection , which is common to all known glucocorticoids.10 ) according to previous studies , gram - negative bacteria , particularly escherichia coli , have been isolated from involved sites of genitourinary malakoplakia in more than two - thirds of patients.11 ) bacteria other than yeast were not isolated in the urine culture in the present case with cystitis because the patient was on antibiotic therapy before admission to our hospital . although we did not carry out a detailed investigation of the patient 's immunity , we believe that unilateral renal malakoplakia extending to the perirenal space and the descending colon , as observed in the present case , may result from an interaction between various factors such as bacterial infection , impaired host immune response and diminished leukocyte function under the influence of a systemic illness such as secondary adrenal insufficiency and diabetes mellitus . the common presenting features of malakoplakia of the kidney are high fever , loin tenderness , and a palpable mass with a history of urinary tract infection.8 ) based on the reported studies , the degree of decreased kidney function varies up to acute renal failure.12,13 ) ultrasound and ct features are variable and only briefly mentioned in many reviews . features include enlarged kidneys,14 ) focal hypoechoic renal masses that simulate abscesses15 ) and heterogeneous masses that calcify , show central areas of necrosis and are mistaken for tumors.16 ) the imaging appearance of malakoplakia is therefore non - specific , and malignant renal tumor is a common misdiagnosis . the final diagnosis of malakoplakia is usually attained only upon histopathologic examination of the excised specimen . there is no established treatment for patients with malakoplakia . however , there are treatment options for malakoplakia that include antibiotics , surgical excision , or a combination of both , depending on the site and extent of involvement . some researchers have suggested that such antibiotics as trimethoprim - sulfamethoxazole and ciprofloxacin were beneficial because of their ability to penetrate intracellularly.8,17 - 20 ) we started the treatment with ciprofloxacin . during follow - up in the outpatient clinic , we changed the antibiotic treatment to trimethoprim - sulfamethoxazole due to the patient 's continued complaint of cystitis symptoms . in conclusion , renal malakoplakia should be taken into account in the differential diagnosis of a patient who presents with urinary tract infection , fever , abdominal pain , and abscess - like lesion in ultrasonography or ct , especially if the patient concerned has diabetes mellitus and a long history of use of exogenous steroids . it is considered that family physicians ' early diagnosis would enable prompt treatment and regular monitoring , leading to avoidance of long - term morbidity and mortality .
malakoplakia is an uncommon but distinctive type of chronic granulomatous inflammation that occurs most commonly in the genitourinary tract , especially the urinary bladder . 
 most patients have associated conditions characterized by some degree of immunosuppression , as seen in solid - organ transplants , autoimmune diseases requiring steroid use , chemotherapy , chronic systemic diseases , alcohol abuse and poorly controlled diabetes . 
 we report an unusual case of the renal malakoplakia that involved the perirenal space , extending to the descending colon in a 65-year - old korean woman with secondary adrenal insufficiency and diabetes mellitus .