pyoderma gangrenosum is among a group of idiopathic neutrophilic dermatosis and is considered a reaction to an internal disease or condition such as inflammatory bowel disease ( both ulcerative and crohn 's disease ) , rheumatoid arthritis and paraproteinaemia . peristomal pyoderma gangrenosum ( ppg ) is a rare subtype of pyoderma gangrenosum that is difficult to diagnose and treat , characterized by the rapid progression of painful necrotic ulcer surrounding an area of abdominal stoma . diagnosis of pyoderma gangrenosum is based on exclusion of other disorders replicating some of its clinical features and histopathological evidence . histopathology is usually nonspecific and characterized by dermal infiltration of neutrophils but helps to exclude other causes of ulceration that may be bacterial or mycobacterial infections , malignancy , vasculitis , and vascular insufficiency . this case report discusses the treatment of a patient with rheumatoid arthritis who developed pyoderma gangrenosum on a background of recent abdominal surgery . eight months following hartmanns procedure for perforated diverticulitis , a 56-year - old lady with a history of severe rheumatoid arthritis presented with a 3 cm large painful , rapidly progressing ulcer surrounding her colostomy site . the patient had consulted the dermatologist 1 month prior to presentation to the surgical unit and was commenced on twice weekly etanercept injections , intralesional triamcinolone , prednisolone , and tacrolimus ointment . testing of the ulcer included polymerase chain reaction for m. ulcerans , herpes multiplex and afb culture  all of which were negative ; site mcs showed evidence of mixed enteric bacteria . after excluding other causes of ulcer and based on clinical presentation the dermatologist concerned about the risk of koebnerizing a second focus of pyoderma , recommended conservative management till pyoderma was completely turned off . figure 1:peristomal pyoderma gangrenosum with presence of necrotizing ulcer near stoma site prior to surgery . the rapidly progressing peristomal ulcer , however , had progressed to form a large cavity with prolapsing granulation tissue and faecal filling in the dependent defect . due to the increased risk of bowel obstruction and faecal peritonitis , a decision was made to surgically debride the ulcer . she was given ivig and iv methylprednisolone 3 days prior to surgery and advised regular immunosuppressants and tacrolimus ointment over wound site post operatively . she had revision of end colostomy with debridement of peristomal ulcer and repair of parastomal hernia . histological results showed evidence of thick neutrophilic and fibrinous surface exudates with an underlying band of fibrous scar ; and presence of reactive fat necrosis . post operatively the patient recovered well with no further surgical complications . at the time of writing the case report it had been 12 months post surgery and patient had no evidence of peristomal ulcer recurrence ( fig . figure 2:healed site of peristomal pyoderma gangrenosum with no evidence of recurrence 12 months post op . healed site of peristomal pyoderma gangrenosum with no evidence of recurrence 12 months post op . approximately 25% of cases are caused by incidental or iatrogenic trauma with 14% of cases of post surgical ppg precipitated by abdominal surgery . in this case ppg was associated with rheumatoid arthritis and occurred within 8 months of abdominal surgery . according to some studies , the time of onset of ppg after surgery can range from 2 months to 25 years . there seems to be a scarcity of randomized controlled trials assessing the optimum treatment for this condition . although tnf blockers , prednisolone , cyclosporine , ivig , or plasmaphoresis and methotrexate have emerged as favourable treatment options , ppg can often be intractable to these conventional therapies . surgical interventions including ulcer debridement and grafting are usually avoided during active phase of disease due to the high risk of triggering the formation of a new lesion at the surgical site . however , there have been a few reports , similar to our case , of successful ppg wound management with surgical intervention . surgical treatment is best performed in selective patients in whom medical management would risk patient mortality .
peristomal pyoderma gangrenosum ( ppg ) is a rare subtype of pyoderma gangrenosum that is difficult to diagnose and treat . 
 it is characterized by the rapid progression of painful necrotic ulcer surrounding an area of abdominal stoma . 
 it is almost exclusively associated with inflammatory bowel disease even after bowel surgery and is associated with significant morbidity . 
 diagnosis of pyoderma gangrenosum is based on exclusion of other disorders replicating some of its clinical features and histopathological evidence.this is a case report of a 56-year - old lady with rheumatoid arthritis who presented with rapidly progressing abdominal ulcer 8 months after a hartmanns procedure for perforated diverticulitis . 
 the ulcer had formed a large cavity causing faecal filling in the dependent defect . 
 the other causes of ulcer were excluded with negative histopathology , negative polymerase chain reaction for mycobacterium ulcerans and negative acid fast bacillus ( afb ) test . 
 she was diagnosed with ppg which is routinely treated medically due to risk of setting off a second focus of pyoderma if surgically intervened . 
 however due to increased risk of faecal peritonitis , it was decided to proceed with surgical debridement . 
 this article will discuss the case in more detail and briefly discuss diagnosis and treatment options for ppg .