Diclofenac-induced Sweet's syndrome

Sir,

A 30-year-old married female is presented in the department of Dermatology with high grade fever, arthralgia, malaise and erythematous plaque on upper back and both upper and lower limbs. She developed such signs and symptoms after 8-10 hrs of taking deep intramuscular injection of diclofenac for right knee joint injury. For this she was admitted to the hospital in the suspicion of drug reaction. There was no history of previous fever with joint pain, abdominal pain or drug eruption, diarrhea, burning micturition or frequency, tuberculosis, diabetes mellitus and hypertension. There was no documented history of taking diclofenac either orally or parenterally in the past.

On examination, multiple tender, erythematous plaques [Figure 1] with pseudovesiculation [Figure 2] were present on upper back, and both upper and lower limbs. There was no lymphadenopathy and hepatosplenomegaly.

Figure 1.

Erythematous plaque of Sweet's syndrome

Figure 2.

The characteristic pseudovesiculation on the lesion of Sweet's syndrome

On blood investigations, the neutrophil count (85%), and ESR and C-reactive protein were raised but rheumatoid factor was negative. Blood sugar and urine examination, blood culture and X-ray of right knee joint were normal.

A 4-mm punch biopsy was taken from the right lower limb and histopathology showed mild spongiosis and flattened rete ridges in epidermis; subepidermis showed moderate edema and diffuse inflammatory infiltrate composed predominantly of neutrophil, with neutrophilic leukocytoclasia [Figure 3]. There was no vasculitis [Figure 4]. At places few lymphocytes and histiocytes were also seen.

Figure 3.

Histopathology (H and E stain-×10) showing marked subepidermal edema with neutrophilic infiltration

Figure 4.

Histopathology (H and E stain-×40) showing dense neutrophilic infitration with leukocytoclasia and without vasculitis

Other systemic pathology was ruled out by various investigations. Based on clinical and histopathological findings diagnosis of Sweet's syndrome was made.

The patient was given oral methyl prednisolone 32 mg daily for 14 days and tapered in next 2 weeks with complete cure in 4 weeks. A 4-month follow-up was uneventful.

The patient was not rechallenged with the diclofenac on ethical ground.

Acute febrile neutrophilic dermatosis is originally described by Robert D. Sweet in 1964.[1] It is an acute disorder that is very rare and most of the time associated with underlying malignancies, autoimmune and inflammatory disorders.[2] Drug-induced Sweet's syndrome is very rare and offending drugs are trimethoprim-sulphamethoxazole, minocyclin, oral contraceptives, all trans retinoic acid, granulocyte colony-stimulating factor, furosemide, hydralazine, and nitrofurantoin. There is only a single case report of diclofenac-induced Sweet's syndrome in which after oral intake of diclofenac and subsequent intense sun exposure lead to acute febrile neutrophilic dermatosis.[3]

In 1996, Walker and Cohen suggested new diagnostic criteria for drug-induced Sweet's syndrome of which the five were required for the confirmation of the diagnosis.[4] All of these criteria are fulfilled in our patient except drug rechallenge which was not possible on ethical ground.

The disease occurs worldwide without any racial predilection, and is not frequently reported in India. A PubMed and IndMed search revealed only 12 cases reported between 1985 and 2002. After that there was a report of bilateral symmetrical bullous Sweet's syndrome in a young male with seasonal recurrence whose etiology was not known.[5] We are presenting a case of diclofenac-induced Sweet's syndrome that has never been reported in India before.