Mona Abdel-Halim

INTRODUCTION: Peripilar sign (PPS) is a trichoscopic sign that was first described in androgenetic alopecia (AGA) and is thought to reflect the presence of perifollicular infiltrate (PFI) in histopathology.

OBJECTIVES: To study PPS in a cohort of patients with AGA and to assess its validity as a sign indicative of PFI.

METHODS: One hundred patients with AGA (confirmed by trichoscopic examination) were recruited in this cross-sectional study. From those patients, frontal scalp biopsy was done for two subgroups, 22 patients with PPS and 23 patients without PPS. Both groups were compared as regards the presence of PFI.

RESULTS: Peripilar sign was present in 50% of the 100 studied cases. No significant difference existed between those with and those without PPS as regards PFI. Peripilar sign was significantly more encountered in patients with skin type III (p=0.001). Its absence was significantly associated with lower interpretability of yellow dots (p<0.001) and their scores were significantly positively correlated (r=0.498, p<0.001). Peripilar sign was significantly associated with absent melanophages histopathologically (p=0.011).

CONCLUSION: Peripilar sign as a trichoscopic sign in AGA does not reflect PFI. It represents a dark color more encountered in patients with lighter skin types. This can be explained by the increased contrast between the dark PPS and the lighter surrounding skin in lighter skin types. Further studies using melanocyte markers and Masson Fontana's stain are needed to further verify the cause of this peri-follicular dark color.

The exact aetiology of pityriasis lichenoides chronica (PLC) remains unknown. While phototherapy is the most investigated therapeutic modality, azithromycin has been used scarcely. The aim of this study is to evaluate the therapeutic efficacy of azithromycin in the treatment of PLC compared to NB-UVB and evaluating the presence of streptococcal infection as a possible etiological factor in PLC patients. The study was designed as a randomised controlled trial. Twenty-four patients with PLC were randomly allocated into either azithromycin (n = 13, standard dose every 10 days) or NB-UVB (n = 11, thrice weekly) groups. End of study (EOS) was either complete clearance of lesions or a maximum of 8 weeks. Therapeutic efficacy was defined as percent reduction in lesions and was calculated for the rash as a whole, erythematous papules alone, and hypopigmented lesions alone and graded into complete, very-good, good, poor or no response. Anti-streptolysin O titre (ASOT), anti-deoxyribonuclease B titre (anti-DNaseB) and throat culture were evaluated at day 0. No significant difference existed between both groups as regards therapeutic efficacy. At EOS, NB-UVB achieved significantly more percent reduction in the extent of hypopigmented lesions and consequently in the rash as a whole (p = 0.001, p = 0.034, respectively). The extent of the rash as a whole was significantly less in the NB-UVB at EOS (p = 0.029, respectively). The effect of NB-UVB on hypopigmented lesions appeared early at week 4 of treatment. Only two patients, one from each group, relapsed during the 3 month follow-up. Evidence of recent streptococcal infection was present in 79% of the cases, mainly in the form of elevated ASOT (94.7%). It was significantly more encountered in young children (< 13 years) (p = 0.03) and was associated with more extent of erythematous papules and consequently with more extent of the rash as a whole (p = 0.05 and p = 0.01, respectively). It did not affect outcome of therapy at EOS. Azithromycin did not show more favorable response in patients with recent streptococcal infection. Therapeutic efficacy of azithromycin is comparable to NB-UVB in treatment of PLC; however, NB-UVB is superior in management of hypopigmented lesions. It is highly suggested that PLC could be a post streptococcal immune mediated disorder.Registration number: ClinicalTrials.gov, NCT03831269.

PURPOSE OF REVIEW: The main purpose of this review is to present newly reported cutaneous manifestations of systemic vasculitis, updates in investigations to verify systemic involvement in cases with cutaneous vasculitis and new therapeutic guidelines. The spectrum of COVID-19-related vasculitis is also covered.

RECENT FINDINGS: Only a few reports highlighted new cutaneous presentations or associations with some systemic vasculitic entities. For example, the association of inflammatory disorders with Takayasu arteritis, the importance of considering Kawasaki disease in febrile children with erythema nodosum, the development of necrotic ulcers on fingers and toes in Behçet's disease and the possible presence of polyarteritis nodosa-like pathological features in vulvar ulcers of Behçet's disease. New attempts to classify cutaneous manifestations of giant cell arteritis (GCA) and antineutrophil cytoplasmic antibody-associated vasculitis (AAV) and the diagnostic investigations for cutaneous vasculitis cases to verify systemic involvement are discussed. Treatment of systemic vasculitis with cutaneous vasculitis should be tailored according to disease status. A plethora of reports in the past 2 years focused on the broad spectrum of COVID-19 vasculitic manifestations.

SUMMARY: Although newly reported cutaneous manifestations of systemic vasculitis are relatively uncommon, the plethora of reports in the past 2 years on COVID-19 vasculitis necessitates the expansion of the classification of vasculitis associated with probable cause to include severe acute respiratory syndrome coronavirus-2 (SARS-Cov-2) vasculitis.

ABSTRACT: Crystalglobulinemia (CG) is a rare disorder characterized by crystallization of monoclonal immunoglobulins in the microcirculation leading to multiorgan vascular thrombosis and ischemic injury. The main cause of CG is multiple myeloma. We report a case of a 52-year-old man who presented with widespread necrotizing plaques and ulcerations. A skin biopsy revealed eosinophilic rectangular-shaped crystals occluding the lumina of blood vessels with no associated features of vasculitis. The crystals were Periodic acid-Schiff stain positive. The findings were diagnostic of CG. Extensive work up lead to the discovery of multiple myeloma. Awareness of CG is important because it may be the first presenting manifestation of an underlying serious hematological malignancy.

BACKGROUND/OBJECTIVES: Pityriasis lichenoides chronica (PLC) lesions are reported to subside with post-inflammatory hypopigmentation (PIH); hence, the most widely perceived nature of hypopigmented macules in PLC is PIH. However, to the best of our knowledge, no studies describing histopathological findings in these lesions are reported in literature. The aim of this study is to evaluate the hypopigmented lesions encountered in PLC patients and to shed light on their histopathological features.

METHODS: A cross-sectional observational study included twenty-one patients with PLC recruited in a period of twelve months. Clinical characteristics of each patient were collected. A skin biopsy from hypopigmented lesions whenever present was taken and assessed with routine haematoxylin and eosin stain.

RESULTS: Seventeen patients (81%) were less than 13 years old. Most patients (85.7%) demonstrated diffuse distribution of lesions. Hypopigmented lesions were present on the face in 12 (57.14%) patients. Histopathologically, hypopigmented lesions showed features of post-inflammatory hypopigmentation in 19% of patients, residual PLC in 52.4% and active PLC 28.6% of patients.

CONCLUSION: Hypopigmented lesions in PLC were noted mainly in younger ages, histopathologically they may show features of active or residual disease, beyond post-inflammatory hypopigmentation. Consequently active treatment for patients presenting predominantly with hypopigmented lesions could be required to control the disease.

Background: Skin involvement in granulomatosis with polyangiitis (GPA) is common and can appear as an initial presentation of the disease or more commonly through its course.

Case presentation: We report a case of a 24-year-old male patient, previously diagnosed as having GPA, admitted with fever, hemoptysis, generalized hemorrhagic blisters associated with arthralgia, fatigue, myalgia, nasal crusting, and vertigo. Three weeks prior to admission, he developed erythematous papules on both elbows, and purpuric papules on both lower limbs. Histopathological examination revealed: interstitial granulomatous dermatitis (elbows) and foci of dermal hemorrhage, foci of interstitial histiocytes and zones of altered necrobiotic collagen (lower limbs) consistent with cutaneous lesions of GPA. Two weeks later, his rash progressed to widespread purpura associated with hemorrhagic blisters. Another biopsy revealed leukocytoclastic vasculitis with fibrinoid necrosis of the vessel walls associated with perivascular infiltrate of neutrophils, nuclear dust and extravasated erythrocytes without an associated granulomatous inflammation or necrobiosis. The constellation of the results of the three biopsies together with clinical correlation pointed to a flare of GPA.

Conclusion: Skin involvement in GPA is quite common, and it can manifest in different forms in the same patient. Our patient developed three different skin pathologies within a short period of time.