Premature graying of hair.

Premature graying is an important cause of low self-esteem, often interfering with socio-cultural adjustment. The onset and progression of graying or canities correlate very closely with chronological aging, and occur in varying degrees in all individuals eventually, regardless of gender or race. Premature canities may occur alone as an autosomal dominant condition or in association with various autoimmune or premature aging syndromes. It needs to be differentiated from various genetic hypomelanotic hair disorders. Reduction in melanogenically active melanocytes in the hair bulb of gray anagen hair follicles with resultant pigment loss is central to the pathogenesis of graying. Defective melanosomal transfers to cortical keratinocytes and melanin incontinence due to melanocyte degeneration are also believed to contribute to this. The white color of canities is an optical effect; the reflection of incident light masks the intrinsic pale yellow color of hair keratin. Full range of color from normal to white can be seen both along individual hair and from hair to hair, and admixture of pigmented and white hair is believed to give the appearance of gray. Graying of hair is usually progressive and permanent, but there are occasional reports of spontaneous repigmentation of gray hair. Studies evaluating the association of canities with osteopenia and cardiovascular disease have revealed mixed results. Despite the extensive molecular research being carried out to understand the pathogenesis of canities, there is paucity of effective evidence-based treatment options. Reports of repigmentation of previously white hair following certain inflammatory processes and use of drugs have suggested the possibility of cytokine-induced recruitment of outer sheath melanocytes to the hair bulb and rekindled the hope for finding an effective drug for treatment of premature canities. In the end, camouflage techniques using hair colorants are outlined.

Onychomycosis: Diagnosis and management.

Onychomycosis is a common nail ailment associated with significant physical and psychological morbidity. Increased prevalence in the recent years is attributed to enhanced longevity, comorbid conditions such as diabetes, avid sports participation, and emergence of HIV. Dermatophytes are the most commonly implicated etiologic agents, particularly Trichophyton rubrum and Trichophyton mentagrophytes var. interdigitale, followed by Candida species and non dermatophytic molds (NDMs). Several clinical variants have been recognized. Candida onychomycosis affects fingernails more often and is accompanied by paronychia. NDM molds should be suspected in patients with history of trauma and associated periungual inflammation. Diagnosis is primarily based upon KOH examination, culture and histopathological examinations of nail clippings and nail biopsy. Adequate and appropriate sample collection is vital to pinpoint the exact etiological fungus. Various improvisations have been adopted to improve the fungal isolation. Culture is the gold standard, while histopathology is often performed to diagnose and differentiate onychomycosis from other nail disorders such as psoriasis and lichen planus. Though rarely used, DNA-based methods are effective for identifying mixed infections and quantification of fungal load. Various treatment modalities including topical, systemic and surgical have been used.Topically, drugs (ciclopirox and amorolfine nail lacquers) are delivered through specialized transungual drug delivery systems ensuring high concentration and prolonged contact. Commonly used oral therapeutic agents include terbinafine, fluconazole, and itraconazole. Terbinafine and itraconazole are given as continuous as well as intermittent regimes. Continuous terbinafine appears to be the most effective regime for dermatophyte onychomycosis. Despite good therapeutic response to newer modalities, long-term outcome is unsatisfactory due to therapeutic failure, relapse, and reinfection. To combat the poor response, newer strategies such as combination, sequential, and supplementary therapies have been suggested. In the end, treatment of special populations such as diabetic, elderly, and children is outlined.