Discussion
Based on clinical, biological, and histological findings, a diagnosis of
SS was established [1]; however, we found an inflammatory infiltrate
rich in PNE. Indeed, the presence of some PNEs in association with
neutrophilic infiltrates during SS has been well documented in the
literature [2]. In a study of 73 cases of SS, the presence of PNE in
association with neutrophilic infiltration was reported in 41% of cases
[2]. However, eosinophil-rich SS is an exception. To the best of our
knowledge, only three cases of eosinophils-rich SS have been reported
[3, 4]. Among these three observations, one case was described in
association with digestive T-cell lymphoma [4]. The clinical and
histological features of the patients are summarized in Table 1.
In our case, the insect bite triggered a cutaneous eruption. So, the
diagnosis of ”exaggerated reactions to insect bites” also called
”Eosinophilic Dermatoses of Hematologic Malignancies” (EDHM) can be
evoked [5].
The present dermatosis seems to be an immunological reaction caused by
sensitization to proteins in insect saliva [5]. It is characterized
by one or multiple erythematous lesions, 2-10 cm in size, which appear a
few hours after the insect bite with progressive extension and
spontaneous healing after 3 to 10 days, without a febrile context
[5]. Histologically, EDHM is characterized by the presence of
numerous PNEs within the dermal infiltrate [5].
We suggest an overlap between
paraneoplastic eosinophil-rich SS and EDHM. Therefore, we believe, that
EDHM can be considered an eosinophil-rich SS.
Conclusion: We report an extremely rare case of SS
characterized by rich dermal infiltration of eosinophils in association
with CLL. Through our case report and the literature, we highlight the
relationship between EDHM and paraneoplastic eosinophil-rich SS to make
the clinician and the anatomopathologist aware of this new entity.