Sweet's syndrome: clinicopathological features of patients treated from 1997 to 2009 at Cassiano Antonio Moraes University Hospital - Vitoria (Espirito Santo)

Sweet or Not? Azathioprine-Induced Sweet Syndrome Mimicking Erythema Nodosum in a Patient With Inflammatory Bowel Disease

This case report highlights the clinical challenge and need to distinguish Sweet syndrome and erythema nodosum (EN) in a 50-year-old woman with newly initiated azathioprine for inflammatory bowel disease. While she initially presented with clinical features concerning for drug-induced Sweet syndrome, a subsequent histopathological examination confirmed early-stage EN. Both Sweet syndrome and EN share common triggers and therapeutic responses, but have distinctive clinical characteristics. Subtle histologic differences also exist in lesion distribution and depth of infiltration. This case underscores the need for accurate differentiation in patients with inflammatory bowel disease to initiate appropriate management and avoid potential complications.

Systematic Review: Sweet Syndrome Associated with Inflammatory Bowel Disease

BACKGROUND AND AIMS

Sweet syndrome [SS] is a dermatological condition associated with both inflammatory bowel disease [IBD] and azathioprine use. We performed a systematic review to better delineate clinical characteristics and outcomes of SS in IBD patients.

METHODS

Peer-reviewed, full-text journal publications from inception to April 2020 in English language and adult subjects with IBD were included. Skin biopsy was required as SS gold-standard diagnosis. Azathioprine-associated SS required recent azathioprine introduction or recurrence of SS after azathioprine re-challenge.

RESULTS

We included 89 publications with 95 patients [mean age of SS diagnosis: 44 years; 59% female; 20 with azathioprine-associated SS and 75 without]. SS was diagnosed prior to IBD in 5.3%, at time of IBD diagnosis in 29.5% and after diagnosis in 64.2%. In total, 91% of patients with SS had known colonic involvement and the majority [76%] had active IBD at diagnosis; 22% had additional extra-intestinal manifestations. Successful therapies for SS included corticosteroids [90.5%], anti-tumour necrosis factor [TNF]-α inhibitor therapy [14.8%] and azathioprine [11.6%]. Azathioprine-associated SS was distinct, with 85% male patients, mean age of SS diagnosis of 50 years and a lower likelihood to be prescribed corticosteroids for treatment [75% vs 94.7% of non-azathioprine-associated SS, p = 0.008]. All patients with azathioprine-associated SS improved with medication cessation and developed recurrence after re-challenge.

CONCLUSIONS

SS may precede or occur with IBD diagnosis in almost one-third of cases. Azathioprine and IBD-associated SS present and behave distinctly, especially with regard to gender, age at diagnosis and recurrence risk. Corticosteroids and TNF-α inhibitors have demonstrated efficacy in treating SS in IBD.

Sweet Syndrome: Clinical Features, Histopathology, and Associations of 83 Cases

BACKGROUND

Sweet syndrome (SS) is an infrequent skin disease characterised by sudden onset of fever, leukocytosis, neutrophilia, and tender erythematous plaques infiltrated by neutrophils. Multiple conditions have been associated with this syndrome.

OBJECTIVES

The aim of this study was to evaluate the clinical, epidemiological, laboratory, and histopathological findings and associations of patients with SS.

METHODS

We conducted a retrospective study of 83 patients with SS followed between January 1, 2006, and January 31, 2015.

RESULTS

Of the patients, 82% were female; the mean age at onset was 48 years. Clinical presentation was mainly characterised by erythematous and edematous plaques, mostly on upper extremities and trunk. Fever was observed in 32%; 60% presented leukocytosis and 39% neutrophilia. On histopathological examination, neutrophilic and lymphohistiocytic infiltrate and edema were the most frequent findings. Fourteen percent of patients had malignancy or hematologic disorders, 26% were classified as having drug-induced SS, and 24% noted recent infection. Only 2 cases occurred during pregnancy. Systemic corticosteroid was the most common choice of treatment, with excellent response. In malignancy-associated SS, the mean hemoglobin level was lower ( P = .01) and the erythrocyte sedimentation rate (ESR) was higher ( P = .04) in comparison to classic and drug-induced SS. Leukocytoclasia was associated with higher risk of recurrence ( P = .01).

CONCLUSION

All patients with SS deserve careful investigation of possible underlying conditions. Higher ESR and lower hemoglobin levels might reinforce the need of malignancy screening. Also, leukocytoclasia appears to be a potential marker of higher recurrence rate, demanding closer and longer follow-up.

Concurrence of Sweet's syndrome, pathergy phenomenon and erythema nodosum-like lesions

We report the case of a 54-year-old woman with concurrent Sweet's syndrome, pathergy phenomenon and eythema nodosum-like lesions associated with suppurative tonsillitis. Tender, violaceous and highly edematous papules and plaques were detected on the forearms and legs, some of which were pseudovesicular. Similar edematous papules were detected on the dorsum of the hands at the sites of intravenous injection. Biopsies of a plaque on the forearm and a papule at the site of intravenous injection confirmed the presence of Sweet's syndrome. Multiple, tender, violet-red, subcutaneous erythematous nodules were revealed on the legs. A biopsy taken from a nodule on the leg revealed septal panniculitis. To our knowledge, no patient with concurrent Sweet's syndrome, pathergy phenomenon, and erythema nodosum-lesions had been reported yet in previous literature.