[Lymphocytic infiltrate of the dermis preceding typical Sweet's syndrome]

Recurrent Idiopathic Sweet Syndrome - Case Report and Literature Review

INTRODUCTION

Sweet syndrome (SS), also denominated as acute febrile neutrophilic dermatosis, is a rare disease characterized by the sudden onset of painful, erythematous, firm skin lesions (papules, plaques, and nodules) which show, upon histologic examination, the presence of a diffuse infiltrate of mature neutrophils. The cutaneous manifestation typically involves the face, neck, trunk, and upper limbs and is associated with fever, general malaise, arthralgia.

CASE REPORT

A female patient, 60 years old, attended the Dermatology Clinic due to the appearance of violaceous erythematous-oedematous infiltrated plaques, located on the face, neck, upper limbs, trunk and knees. The onset of the cutaneous manifestation had occurred 2 months prior, accompanied by pain, chills, flares of fever and arthralgia. The onset coincided with the surgical treatment of an umbilical hernia. From the medical history we note that the patient was diagnosed in 2014 with histiocytoid SS. She followed a treatment with methylprednisolone, with positive response, but had many relapses after the discontinuation of treatment. In 2017, due to a new episode, the histopathological examination was repeated, which revealed classical SS. She received treatment with Disulone and Colchicine. She had not been administered any treatment throughout the previous year. Laboratory tests revealed leukocytosis with neutrophils, increased ESR, elevated C4, hyperglycemia. The current histopathological examination revealed lymphocytic SS. Under treatment with methylprednisolone 32mg/day, the evolution was favorable.

DISCUSSIONS

The first case of SS was described by Robert Douglas Sweet in 1964. As known aetiological factors there have been described gastrointestinal and urinary tract infections, pregnancy, inflammatory bowel disease, drugs or malignancies. There have been described cases of SS that appeared after surgical treatment, as in our case, which registered a new outbreak following the umbilical hernia treatment. The histopathological variants of SS described in the literature are: subcutaneous, eosinophilic, histiocytoid, lymphocytic type. The first line-therapy consists in systemic corticosteroids, which induce a fast remission of lesions and general symptoms. Recurrence may occur in approximately 50% of patients and is common in idiopathic or paraneoplastic cases.

CONCLUSIONS

In addition to the neutrophilic infiltrate that is typical for Sweet syndrome, different types of histological manifestations have been described in the literature: subcutaneous, eosinophilic, histiocytoid, lymphocytic. In our case, we noted that the histological profile changed over time, from a histiocytoid SS recorded in 2014, to a classical SS in 2017, followed by the appearance of lymphocytic SS in 2019. Due to the fact that SS can be associated with a numerous other disorders, our patient requires regular monitoring with a view to eliminate them, and potentially to make a diagnosis and initiate early specific treatment.

Histiocytoid Sweet Syndrome Is More Frequently Associated With Myelodysplastic Syndromes Than the Classical Neutrophilic Variant: A Comparative Series of 62 Patients

Histiocytoid Sweet syndrome (H-SS) is a histological variant of Sweet syndrome (SS) differing from classical neutrophilic SS (N-SS) by a dermal infiltrate mainly composed of lymphocytes and histiocytoid myeloperoxidase-positive cells. We aimed to report a large series of H-SS and compare the frequency and type of hematological malignancies associated to H-SS and N-SS. We included 62 patients with a coding histopathologic diagnosis of SS prospectively registered between 2005 and 2014 in the database of our Department of Pathology. Overall, 22 (35.5%) and 40 (64.5%) patients had a histological diagnosis of H-SS and N-SS, respectively. Median age, sex ratio, and cutaneous lesions were similar in the 2 groups. The frequency of extra-cutaneous manifestations was similar (50% vs 37.5%, P = 0.42). Recurrent forms were significantly more frequent in H-SS than in N-SS patients (21% vs 2.5%, P = 0.01). A hematological malignancy was diagnosed in 22 patients, 12 (55.5%) with H-SS and 10 (25%) with N-SS (P = 0.019). Hematological malignancy was of myeloid origin in 8/22 (36.3%) H-SS and 5/40 (12.5%) N-SS patients (P = 0.02), and of lymphoid origin without myeloid component in 4/22 (18.1%) H-SS and 4/40 (10%) N-SS patients (P = 0.35), respectively. One N-SS patient had a hematological malignancy of mixed (myeloid and lymphoid) phenotype. A myelodysplastic syndrome (MDS) was diagnosed in 7/22 (31.8%) H-SS and 1/40 (2.5%) N-SS patients (P < 0.001). Hematological disease was diagnosed before (in 8 H-SS and 3 N-SS patients) or at the time of the occurrence of the cutaneous lesions (in 1 H-SS and 7 N-SS patients). However, in 3 H-SS patients, all with MDS, cutaneous lesions preceded the hematological disease by ≤6 months. In conclusion, H-SS was associated with MDS in one third of patients but also with lymphoid malignancies, and cutaneous lesions could precede the hematological diagnosis in patients with MDS. A complete hematological assessment is mandatory at diagnosis, and monitoring blood cell counts should be recommended for at least 6 months after the diagnosis of H-SS.

Initially lymphocytic Sweet's syndrome in male patients with myelodysplasia: a distinguished clinicopathological entity? Case report and systematic review of the literature

BACKGROUND

Sweet's syndrome (SS) is an acute febrile neutrophilic dermatosis. It can occur as an idiopathic, drug-induced or malignancy-associated entity. SS is also seen in patients with myelodysplastic syndrome (MDS) where it may present atypically, both clinically and histologically. In a few rare cases of MDS, lymphocytic infiltrates are the presenting feature of SS.

METHODS

MEDLINE and Scopus were the data sources for our review.

RESULTS

A clinicopathological subsetemerged of 12 male SS patients with MDS and a mean age of 67.3 years in which the initial SS lesions were lymphocytic infiltrates. However, from 0.5 to 8 years later, sequential biopsies revealed neutrophilic dermal infiltration typical of SS.

CONCLUSION

Initially lymphocytic infiltrates in this subset could be attributed either to an early timing of the biopsy concerning the age of the lesion or to the dysgranulopoiesis syndrome. A possible relationship between the dysfunction of the receptor of the granulocyte-macrophage colony stimulating factor, the gene of which is located on the pseudoautosomal X-Y region, may exist in MDS patients with initially lymphocytic SS. This could explain the male gender of this subset and might establish initially lymphocytic SS as a distinguished clinicopathological entity for predicting the occurrence and even the prognosis of MDS.