Bullous Pyoderma Gangrenosum

Pyoderma gangrenosum (PG) is a rare neutrophilic dermatosis characterized by painful necrotic ulcerations. It affects patients between the age of 40 and 60 years. Clinically, it presents as a very painful papulopustule or bulla which rapidly progresses to form deep necrotic ulcers. Hematologic malignancies are commonly linked with bullous PG. We report a case of bullous PG who presented with multiple haemorrhagic blisters without any systemic associations.


INTRODUCTION
yoderma gangrenosum (PG) is a sterile neutrophilic dermatosis of unidentified etiology affecting patients between 40 to 60 years (1). Women are more commonly affected than men. Pyoderma gangrenosum (dermatitis gangrenosa, phagedenic pyoderma; 2) was first described by Brocq in 1916 (3). Pain is often excruciating and out of proportion to the size of the ulcer. It is frequently associated with other systemic diseases like inflammatory bowel disease (IBD), rheumatological disorders, haematological abnormalities, connective tissue disorders. PG is often a clinical diagnosis. There is no specific HPE or laboratory findings to confirm the diagnosis.

CASE REPORT
47-year-old male patient presented to our out-patient department with complaints of fever and multiple dark coloured fluid filled lesions on both hands for 3 days. Lesions initially started on the right palm as papulopustule which rapidly spread to involve the left palm, dorsal aspect of both hands and finger tips and were associated with severe pain. Few lesions burst on its own leaving behind erosions. There was no history of trauma, no history of any topical application, and no history of any drug intake. There was no history of joint pain, abdominal pain, diarrhoea, loss of appetite, weight loss. There was no similar complaints in the family.
Dermatological examination revealed multiple discrete well-defined tender tense haemorrhagic bullae on the palmar aspect of both hands. A single bulla was noted on the dorsal aspect of either hands. Few tender necrotic shallow ulcers of varying size with surrounding violaceous induration and crusting noted on the palmar aspect of both hands. Dactylitis of fingers was noted over both hands. No similar lesions were noted elsewhere in the body. Examination of soles, Oral mucosa, genital mucosa, scalp and nails were normal. Systemic examination was found to be normal. Differential diagnosis of bullous PG, bullous FDE, bullous contact dermatitis, erythema multiforme were made. Baseline investigations like CBC, RBS, RFT, LFT, urine analysis, chest x ray, ECG, peripheral smear were done. Total counts, ANC and ESR were found to be elevated. Gram stain from the wound revealed few neutrophils with no microorganisms. Blood and skin cultures were negative.
As patient did not have any clinical symptoms like bone pain, recurrent infections, frequent fractures, loss of weight, loss of appetite and as laboratory investigations revealed absence of anemia, hypercalcemia, normal creatinine, normal albumin levels, no rouleaux formation in peripheral smear, serum protein electrophoresis was deferred. Skin biopsy revealed stratified squamous epithelium with hyperkeratosis, parakeratosis, exocytosis and ulceration covered by inflammatory exudate. The dense inflammatory exudate extends to the deeper region with focal micro abscesses. Based on clinical presentation, diagnosis of pyoderma gangrenosum was made.
Patient was started on IV steroids, IV antibiotics to prevent secondary infection and analgesics along with local wound care. Patient showed rapid response to steroids within 3 days. IV Steroids was changed to oral steroids which was tapered slowly and stopped. Complete remission was obtained within 2 months and patient continued to be under remission during the follow up period of 4 months.

DISCUSSION
Pyoderma gangrenosum (PG) is a rare idiopathic sterile neutrophilic skin dermatosis characterized by an ulcer which is extremely painful. Lesions typically begin as tender papulopustules, nodules or plaques that rapidly evolved into shallow or deep ulcers with violaceous, undermined borders with surrounding zone of erythema. Pathergy is commonly observed in PG (4). It heals with atrophic or cribriform pigmented scars. The common sites of occurrence are lower extremities, buttocks and perineal region (5). In our case patient presented with palmar involvement which is a rare site of occurance. Extra cutaneous sites include lungs, musculoskeletal system, spleen, eye (6)(7)(8)

CONCLUSION
Bullous PG is a not so common variant of PG. Haematologic malignancies should be excluded in bullous type of PG. In our case patient showed good response to steroids and there was no evidence of systemic associations or hematological malignancies.