Pure Bullous Pyoderma Gangrenosum, a Challenging Clinico-Pathological Diagnosis: Critical Literature Review with Emphasis on Diagnostic Criteria.

Pyoderma gangrenosum (PG) is an uncommon, idiopathic, neutrophilic dermatosis characterised by large necrotic ulcers. Occasionally, patients develop atypical presentations, including pustular, bullous, and vegetative lesions. Bullous pyoderma gangrenosum (BPG) is considered an extremely rare form. We describe a case of BPG in a 76-year-old man, with active oncological history, including a recent diagnosis of hairy cell leukemia. Diagnosis of PG was delayed because of atypical clinical presentation that mimicked necrotising fasciitis. The patient was treated with diverse intravenous antibiotics and several surgical procedures. The suspicion of neutrophilic dermatosis arose from the histopathological studies. In the setting of mandatory clinico-pathological correlation, the aim of this report is to point out the morphological characteristics that allow recognition of this uncommon variant of pyoderma gangrenosum.

Imiquimod-enhanced immunotherapy with diphencyprone for patients with alopecia areata.

Topical immunotherapy with dyphencyprone (DPCP) is widely used in patients with alopecia areata (AA). It can produce a contact dermatitis that is believed to decrease Th1 response, predominant in AA. It has been shown that imiquimod (IMQ), a topical immunomodulator drug, can produce sensitization to DPCP in patients that do not show signs of contact dermatitis when exposed to DPCP. Nevertheless, there is no evidence as to whether it can improve DPCP efficacy in already sensitized patients. We present a series of 9 patients, (7 females [77%] and 2 males [22%]) with a mean age of 38.4 years (range, 19-60 years), successfully sensitized to DPCP, that were treated with a combination of DPCP and IMQ. The mean SALT (Severity of Alopecia Tool) score before adding IMQ was 43.3 (range, 10-60), and the mean number of months of DPCP use prior to the addition of IMQ was 6.8 (range 0-10). After adding IMQ to their DPCP treatment, 77% of the patients had further improvement, with a mean SALT reduction of 13.3 (range, [-50] - 40), and a mean duration of response of 5.2 months. No adverse effects were reported. According to this data, we believe that the combination of DPCP and IMQ can be a promising way of improving the efficacy of contact immunotherapy in AA, and requires further study.

A patient with COVID-19 and a skin rash.

A woman presented to the emergency department during the COVID-19 pandemic, reporting a slightly pruritic rash that had developed five days after the onset of fever, cough and malaise.

Acute telogen effluvium associated with SARS-CoV-2 infection.

Acute telogen effluvium has been recognised as a dermatological sequela of COVID-19.