Background: Hair follicle miniaturization is the hallmark of male pattern hair loss (MPHL), female pattern hair loss (FPHL), and alopecia areata (AA). AA has the potential for complete hair regrowth and reversal of miniaturization. MPHL and FPHL are either irreversible or show only partial regrowth and minimal reversal of miniaturization. Hypothesis: The arrector pili muscle (APM) attachment to the hair follicle bulge, a recognized repository of stem cells may be necessary for reversal of hair follicle miniaturization. Materials and Methods: Sequential histological sections from MPHL, FPHL, AA, and telogen effluvium were used to create three-dimensional images to compare the relationship between the APM and bulge. Results: In AA, contact was maintained between the APM and the bulge of miniaturized follicles while in MPHL and FPHL contact was lost. Discussion: Contact between the APM and the bulge in AA may be required for reversal of hair follicle miniaturization. Maintenance of contact between miniaturized follicles in AA could explain the complete hair regrowth while loss of contact between the APM and the bulge in MPHL and FPHL may explain why the hair loss is largely irreversible. This loss of contact may reflect changes in stem cell biology that also underlie irreversible miniaturization.

Background: Trichothiodistrophy (TTD) is a rare autosomal recessive condition that is characterized by a specific congenital hair shaft dysplasia caused by deficiency of sulfur associated with a wide spectrum of multisystem abnormalities. In this article, we study clinical, microscopic, and ultrastructural findings of 20 patients with TTD with the aim to add further insights regarding to this rare condition. Additionally, analyses of our results are compared with those extracted from the literature in order to enhance its comprehensibility. Materials and Methods: Twenty cases of TTD were included: 7 from Mexico and 14 from Spain. Clinical, microscopic, scanning electron microscopy (SEM) studies and X-ray microanalysis (XrMa) were carried out in all of them. Genetic studies were performed in all seven Mexican cases. Patients with xeroderma pigmentosum and xeroderma pigmentosum/TTD-complex were excluded. Results: Cuticular changes and longitudinal crests of the hair shaft were demonstrated. These crests were irregular, disorganized, following the hair longest axis. Hair shaft sulfur deficiency was disposed discontinuously and intermittently rather than uniformly. This severe decrease of sulfur contents was located close to the trichoschisis areas. Only five patients did not show related disturbances. Micro-dolichocephaly was observed in five cases and represented the most frequent facial dysmorphism found. It is also remarkable that all patients with urologic malformations also combined diverse neurologic disorders. Moreover, three Mexican sisters demonstrated the coexistence of scarce pubic vellus hair, developmental delay, onychodystrophy, and maxillar/mandibullar hypoplasia. Conclusions: TTD phenotype has greatly varied from very subtle forms to severe alterations such as neurologic abnormalities, blindness, lamellar ichthyosis and gonadal malformations. Herein, a multisystem study should be performed mandatorily in patients diagnosed with TTD.

Many reports have described the presence of alopecia areata (AA) associated with other autoimmune diseases, which support the autoimmune nature of AA. Additionally, AA has been reported in association with malignancy as a paraneoplastic symptom. In this report, we describe three patients with diffuse large B-cell lymphoma, alveolar soft part sarcoma, and cavernous sinus arteriovenous fistula with embolization treatment, respectively, who characteristically presented with rectangular-patterned occipital AA.

Ectodermal dysplasias (ED) are a group of inherited disorders characterized by dysplasia of structures of ectodermal origin, clinically classified into hypohidrotic and hidrotic forms. A 21-year-old female presented with history of hypohidrosis, thinning of scalp and eyebrow hair, xerotic skin, and periorbital and perioral wrinkling. There was hypodontia and peg-shaped teeth on intraoral examination. Routine investigations were normal, orthopantomogram revealed absence of multiple teeth with peg-shaped teeth. Histopathological examination showed thinned epidermis and reduction in the number of eccrine units. Thus, the diagnosis was confirmed as Hypohidrotic ED.

Alopecia is a rare manifestation of Hodgkin's disease. It may be due to follicular destruction due to direct infiltration by the disease, or it may be a secondary or paraneoplastic manifestation. In this patient, hair loss, diffuse yperpigmentation, and generalized itching preceded other manifestations of the disease. The pattern of hair loss was diffuse and generalized in nature involving scalp, eyebrows, axilla, and groin. Subsequently, the patient was diagnosed to be a case of Hodgkin's lymphoma, based on clinical and histopathological features. Earlier reports on alopecia accompanying Hodgkin's disease have also been discussed. This case highlights the importance of keeping a high suspicion of an underlying malignancy in patients presenting with such cutaneous manifestations.

We report the dermoscopic features of pemphigus vulgaris (PV) involving the scalp of a 57-year-old African-American female. Among our findings, there were hair casts - movable tubular structures that envelop the hair shafts. We suggest that the development of those casts occurs through acantholysis within the outer root sheath, a mechanism not yet considered in the literature. This report also highlights how dermoscopy may contribute to the evaluation of disease activity, especially in those cases of PV in which scalp involvement is recalcitrant to treatment. Finally, we recommend that the presence of hair casts should herald the need of therapy adjustment for better disease control.

A 45-year-old man was treated with WHO multibacillary multidrug therapy for borderline leprosy and high dose daily Clofazimine for lepra reaction. Along with the expected side effect of skin pigmentation, the patient also noticed darkening of previously grey hair. This colour persisted eight months after completing multibacillary multidrug therapy.

Trichotillomania is as medical condition caused by the patient himself by pulling out of is own hair, resulting in a perceptible hair loss pattern that frequently is associated with other psychiatric processes. Generally has a chronic course in most patients, and a challenging therapeutical management. There are several available options for is treatment, but the clinical response is not satisfactory in many patients. Recently, N-acetylcisteine, a glutamate modulator, has shown efficacy in the treatment of trichotillomania and other compulsive behaviors, and is considered a new alternative in the management of this condition. We describe two patients with trichotillomania successfully treated with N-acetylcysteine. Nevertheless, further studies need to be conducted to establish the appropriate treatment regimen and to evaluate it long-term efficacy in improving this chronic condition.

Madarosis is window of diagnosis to various diseases and disorders. Though the patient presents to the dermatologist or the ophthalmologist for the treatment of this disease, a consultation with various other departments is necessary for the accurate diagnosis and treatment of this condition. Madarosis occurs in leprosy frequently but its occurrence as a presenting manifestation of leprosy has seldom been reported. Here, we are presenting a case of lepromatous leprosy who presented with bilateral madarosis only with no obvious skin lesions of leprosy.

Congenital alopecia includes a broad differential diagnosis and presents a diagnostic and therapeutic challenge for the physician. Congenital atrichia is a rare form of irreversible alopecia that is usually inherited as an autosomal recessive pattern. We report a 2-year-old male child presenting with total alopecia of scalp, eyebrows, eyelashes, and body hair since birth. The child had cardiac malposition with situs inversus of the viscera. Computed tomography of the chest and abdomen revealed median position of the heart with transposition of abdominal viscera. To our knowledge, this is the first case of congenital atrichia associated with situs inversus and mesocardia.