Hair Loss and Telogen Effluvium Related to COVID-19: The Potential Implication of Adipose-Derived Mesenchymal Stem Cells and Platelet-Rich Plasma as Regenerative Strategies.

The diffusion of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) inducing coronavirus disease 2019 (COVID-19) has increased the incidence of several dermatological disorders, including hair loss (HL). This article aims to review the literature regarding the incidence of HL and telogen effluvium (TE) in COVID-19 patients and critically appraise the available evidence regarding the role of regenerative strategies like Platelet-Rich Plasma (PRP) and Human Follicle Stem Cells (HFSCs). A literature review regarding the correlation of HL and TE in COVID-19 patients analyzing the biomolecular pathway involved and the role of regenerative strategies was performed using PubMed, MEDLINE, Embase, PreMEDLINE, Scopus, and the Cochrane databases. Observational studies revealed an escalated incidence of pattern HL and TE in COVID-19 patients. Psychological stress, systemic inflammation, and oxidative stress are potential culprits. Proinflammatory cytokines and stress hormones negatively affect the normal metabolism of proteoglycans. Reduced anagenic expression of proteoglycans is a potential mediating mechanism that connects HL to COVID-19. Currently, only one study has been published on PRP against HL in COVID-19 patients. Further controlled trials are required to confirm PRP and HFSCs efficacy in COVID-19 patients.

What can the hair tell us about COVID-19?

The novel viral pandemic coronavirus disease 2019 (COVID-19) has sparked uncertainties as to its origin, epidemiology and natural course. The study of the cutaneous manifestations of COVID-19 has evolved with the hope that they may be useful as markers for the disease, prognostication and pathogenic insights into the disease. With regard to the hair, clinicopathological correlations have remained elusive. More recently, androgenetic alopecia and grey hair have been proposed as cutaneous markers for elevated severity risk. So far, we have only observed postinfectious effluvium in a causal association with COVID-19. The onset and acuity of hair shedding depended on the clinical severity of disease. There was complete recovery of hair.

Diagnostic exercise: generalized alopecia and mural folliculitis in a goat.

An 18-month-old cross-bred goat was presented with generalized erythema and thinning of the hair coat, as well as localized moderate scaling. Histopathological evaluation of skin biopsies showed hyperplasia and marked disruption of the infundibular epithelium owing to a predominant infiltrate of macrophages with multinucleated histiocytic giant cells and some lymphocytes, plasma cells, and eosinophils. Examination of peripheral blood and skin by polymerase chain reaction gave positive results for ovine herpesvirus type 2 consistent with a diagnosis of malignant catarrhal fever.

Lichen planus and other cutaneous manifestations in chronic hepatitis C: pre- and post-interferon-based treatment prevalence vary in a cohort of patients from low hepatitis C virus endemic area.

BACKGROUND: Several controversies exist regarding the relationship between hepatitis C virus (HCV) infection and some cutaneous manifestations, lichen planus (LP) in particular. OBJECTIVES: To determine the prevalence of LP and other cutaneous manifestations in a cohort of patients infected with HCV from low HCV endemic area of Slovenia, to correlate findings with chosen biological variables and to assess the role of interferon (IFN)-based treatment of HCV infection in cutaneous manifestations. Methods A total of 171 consecutive HCV-seropositive patients and 171 HCV-seronegative age- and gender-matched controls were studied prospectively. Prevalence of cutaneous manifestations, comparison between study patients and controls and correlation of skin findings with demographic, biochemical, virological and liver histologic findings as well as IFN-based therapy were assessed. RESULTS: Overall presence of LP in HCV-seropositives was 2.3%; although LP was not found in controls, the difference was not statistically significant (P = 0.123). Significantly higher than in controls was the prevalence of pruritus (31.0%, P < 0.001), dry skin (16.4%, P < 0.001) and hair loss (9.9%, P < 0.001). In IFN-based treatment naïves, skin findings were more frequent compared with controls, but not significantly, with no correlation to chosen biological variables. Current IFN-based treatment was significantly connected to pruritus (P < 0.001) and dry skin (P < 0.001). Compared with treatment naïves, in post-treated patients pruritus (odds ratio, 19.13; 95% confidence interval, 6.85-53.42; P < 0.001), dry skin (odds ratio, 4.21; 95% confidence interval, 1.44-12.31; P < 0.001) and hair loss (P < 0.001) were significantly more common. CONCLUSIONS: LP was not significantly related to HCV infection. Prevalence of pruritus, dry skin and hair loss was significantly higher in post-compared with pre-treated patients. The role of IFN in post-treatment persistence of skin manifestations needs to be assessed.

European brown hare syndrome in wild European brown hares from Greece.

From 1999 to mid-2003, 97 European brown hares (Lepus europaeus) found dead throughout Greece were examined by necropsy, histopathology, and reverse-transcription polymerase chain reaction (RT-PCR) for the presence of European brown hare syndrome (EBHS) and EBHS virus (EBHSV), respectively. Hare losses were sporadic, starting in the cold season and lasting for many months (December to May). The most prominent gross lesions were observed in the liver and included swelling and discoloration; congestion and hemorrhages were present mainly in lungs and tracheal mucosa. Necropsy findings were suggestive of EBHS, which was confirmed by histopathology and RT-PCR. This study documents, for the first time, EBHS in Greece.

Viral-associated trichodysplasia in patients who are immunocompromised.

Viral-associated trichodysplasia of immunosuppression is a newly described clinicopathologic entity found in patients who are undergoing drug-induced immunosuppression to prevent organ transplant rejection. Patients have numerous erythematous papules concentrated in the central portion of the face and variable degrees of hair loss, most severely affecting facial hair. Histologic findings of facial papules are highly distinctive and unique, and suggest that the entire machinery of the follicular bulb is devoted to the manufacture of inner root sheath-type keratin. Electron microscopy reveals intranuclear viral particles, but precise viral identification has not yet been achieved.

Mural folliculitis and alopecia caused by infection with goat-associated malignant catarrhal fever virus in two sika deer.

Two sika deer from a zoo in Florida were examined because of chronic hair loss and skin lesions. No common causes of alopecia were identified in either deer. One deer was treated with prednisone, but the condition worsened when the dosage was decreased. Both deer were euthanatized after several months because of continued disease. The predominant histologic lesion in skin specimens was granulomatous mural folliculitis. Serologic testing and sequencing of fragments produced with a consensus polymerase chain reaction assay indicated that both deer were infected with caprine herpesvirus-2, a newly recognized member of the malignant catarrhal fever group of viruses. Disease in these deer was substantially different from that typically seen following infection with ovine herpesvirus-2, the sheep-associated malignant catarrhal fever virus. Findings in these deer establish the pathogenicity of caprine herpesvirus-2 in sika deer and illustrate the ability of this group of complex herpesviruses to cause a wide variety of clinical abnormalities in diverse species.

Scarring alopecia and sclerodermatous changes of the scalp in a patient with hepatitis C infection.

Hepatitis C virus (HCV) is a common cause of chronic hepatitis and is frequently associated with extrahepatic disease. Recently, cutaneous disorders have been a presenting manifestation of HCV infection. Porphyria cutanea tarda (PCT) is one of the cutaneous diseases associated with hepatitis C. PCT manifests in an acute form with tense bullae and erosions and in a chronic form with milia, scarring, and sclerodermatous changes. HCV has also been implicated as a cause of vasculitis through immune complex deposition. We report a patient in whom HCV was associated with sclerodermoid PCT and a medium vessel vasculitis. This case underscores the importance of HCV and its potential cutaneous manifestations, as well as the importance of recognizing cutaneous manifestations of internal disease that may be the first clue to diagnosis of HCV.