Dermoscopy - a simple and rapid in vivo diagnostic technique for tinea incognito

Abstract Tinea incognito resulting from corticosteroid abuse is becoming very common in the tropics. Its diagnosis is tricky owing to its confusing morphology, as well as practical and technical issues associated with mycological tests. Dermoscopy has now evolved as a novel diagnostic tool for diagnosing tinea incognito in such challenging situations, since the typical hair changes such as Morse-code hairs, deformable hairs, translucent hairs, comma and cork screw hairs, and perifollicular scaling may be seen despite steroid use, irrespective of mycological results.

Glutathione as a skin whitening agent: Facts, myths, evidence and controversies.

Glutathione is a low molecular weight thiol-tripeptide that plays a prominent role in maintaining intracellular redox balance. In addition to its remarkable antioxidant properties, the discovery of its antimelanogenic properties has led to its promotion as a skin-lightening agent. It is widely used for this indication in some ethnic populations. However, there is a dichotomy between evidence to support its effi cacy and safety. The hype around its depigmentary properties may be a marketing gimmick of pharma-cosmeceutical companies. This review focuses on the various aspects of glutathione: its metabolism, mechanism of action and the scientifi c evidence to evaluate its effi cacy as a systemic skin-lightening agent. Glutathione is present intracellularly in its reduced form and plays an important role in various physiological functions. Its skin-lightening effects result from direct as well as indirect inhibition of the tyrosinase enzyme and switching from eumelanin to phaeomelanin production. It is available in oral, parenteral and topical forms. Although the use of intravenous glutathione injections is popular, there is no evidence to prove its effi cacy. In fact, the adverse effects caused by intravenous glutathione have led the Food and Drug Administration of Philippines to issue a public warning condemning its use for off-label indications such as skin lightening. Currently, there are three randomized controlled trials that support the skin-lightening effect and good safety profi le of topical and oral glutathione. However, key questions such as the duration of treatment, longevity of skin-lightening effect and maintenance protocols remain unanswered. More randomized, double-blind, placebo-controlled trials with larger sample size, long-term follow-up and well-defi ned effi cacy outcomes are warranted to establish the relevance of this molecule in disorders of hyperpigmentation and skin lightening.

Nocebo effect in dermatology.

Nocebo effect, originally denoting the negative counterpart of the placebo phenomenon, is now better defined as the occurrence of adverse effects to a therapeutic intervention because the patient expects them to develop. More commonly encountered in patients with a past negative experience, this effect stems from highly active processes in the central nervous system, mediated by specifi c neurotransmitters and modulated by psychological mechanisms such as expectation and conditioning. The magnitude of nocebo effect in clinical medicine is being increasingly appreciated and its relevance encompasses clinical trials as well as clinical practice. Although there is hardly any reference to the term nocebo in dermatology articles, the phenomenon is encountered routinely by dermatologists. Dermatology patients are more susceptible to nocebo responses owing to the psychological concern from visibility of skin lesions and the chronicity, unpredictable course, lack of ‘permanent cure’ and frequent relapses of skin disorders. While fi nasteride remains the prototypical drug that displays a prominent nocebo effect in dermatologic therapeutics, other drugs such as isotretinoin are also likely inducers. This peculiar phenomenon has recently been appreciated in the modulation of itch perception and in controlled drug provocation tests in patients with a history of adverse drug reactions. Considering the confl ict between patients’ right to information about treatment related adverse effects and the likelihood of nocebo effect stemming from information disclosure, the prospect of ethically minimizing nocebo effect remains daunting. In this article, we review the concept of nocebo effect, its postulated mechanism, relevance in clinical dermatology and techniques to prevent it from becoming a barrier to effective patient management.

Female pattern hair loss.

Female pattern hair loss (FPHL) is a common cause of hair loss in women characterized by diffuse reduction in hair density over the crown and frontal scalp with retention of the frontal hairline. Its prevalence increases with advancing age and is associated with significant psychological morbidity. The pathophysiology of FPHL is still not completely understood and seems to be multifactorial. Although androgens have been implicated, the involvement of androgen-independent mechanisms is evident from frequent lack of clinical or biochemical markers of hyperandrogenism in affected women. The role of genetic polymorphisms involving the androgen and estrogen receptors is being increasingly recognized in its causation and predicting treatment response to anti-androgens. There are different clinical patterns and classifications of FPHL, knowledge of which facilitates patient management and research. Chronic telogen effluvium remains as the most important differential diagnosis. Thorough history, clinical examination, and evaluation are essential to confirm diagnosis. Patients with clinical signs of androgen excess require assessment of biochemical parameters and imaging studies. It is prudent to screen the patients for metabolic syndrome and cardiovascular risk factors. The treatment comprises medical and/or surgical modalities. Medical treatment should be initiated early as it effectively arrests hair loss progression rather than stimulating regrowth. Minoxidil continues to be the first line therapy whereas anti-androgens form the second line of treatment. The progressive nature of FPHL mandates long-term treatment for sustained effect. Medical therapy may be supplemented with cosmetic concealment in those desirous of greater hair density. Surgery may be worthwhile in some carefully selected patients.

Cutaneous tuberculosis in children: The Indian perspective.

Cutaneous tuberculosis continues to be a significant medical problem even with the advent of highly effective antituberculous drugs. It constitutes about 1.5% of all extra pulmonary tuberculosis. The prevalence in children varies from 18 to 54% in India. There is no gender predilection and the infection occurs with increased frequency in 10-14 year age group. Intrafamilial source of TB has been observed very frequently. A concomitant TB lymphadenitis is most common while involvement of other systemic organs like lung, bone and abdomen has also been observed. Protective efficacy of BCG is debatable and not yet fully defined. Of all the clinical types, scrofuloderma (SFD) is the most commonly encountered variant followed by lupus vulgaris (LV) and tuberculosis verrucosa cutis (TBVC). Lichen scrofulosorum (LS) is generally found to be associated with systemic TB focus in about 72% of cases. The impact of HIV on childhood cutaneous TB seems to be minimal. Similar to adults, the diagnosis of cutaneous tuberculosis relies mainly on histopathology, culture on LJ medium or radiometric BACTEC 460 TB culture system and PCR. In addition Mantoux positivity and a positive therapeutic trial with anti-tubercular drugs may be a good pointer to tubercular infection. A thorough clinical evaluation and exhaustive investigations to pin-point associated systemic focus is advocated as the latter has an impact on the duration of treatment. Cutaneous TB in children is treated as per the recommendations of therapy for extrapulmonary TB.

Mortimer's Malady revisited: A case of polymorphic cutaneous and systemic sarcoidosis.

Sarcoidosis is a systemic disorder with prominent cutaneous component. Skin lesions are of diverse morphology, of which few are specific for the disease. We describe a 30-year-old woman with polymorphic skin lesions including papules, plaques, and nodules, as well as uncommon variants like eyelid papules, palmar and digital nodules, tattoo sarcoid, as well as scar sarcoid. The patient also had stage II pulmonary sarcoidosis, and articular as well as reticulo-endothelial system involvement manifested by enlarged mediastinal and abdominal lymph nodes and hepatosplenomegaly. The presentation of polymorphic skin lesions with involvement of multiple extra-cutaneous systems is uncommon in a single patient.