Jarisch‒Herxheimer reaction.

Syphilis is caused by a spirochete, Treponema pallidum. Diagnosis of syphilis is made with a venereal disease research laboratory test. Treatment of choice is intramuscular injection benzathine Penicillin. The Jarisch‒Herxheimer reaction (JHR) is a transient immunological phenomenon that can occur in patients during treatment for syphilis with penicillin. It is a rare phenomenon but can be a potentially severe one. It manifests clinically with short-term constitutional symptoms such as fever, chills, headache, and myalgia, besides exacerbation of existing cutaneous lesions. We report the case of a 24-year-old man presenting with JHR posttreatment with benzathine penicillin.

Eosinophilic Granulomatosis with Polyangiitis.

Eosinophilic granulomatosis with polyangiitis also known as Churg-Strauss syndrome or allergic granulomatosis and angiitis is an extremely rare systemic necrotizing vasculitis that affects small-to-medium-sized vessels. Here, we report a case of a 58-year-old man presenting with painful swelling of bilateral lower limbs with multiple well-defined erosions on lower legs and dorsum of the foot with a few of them showing brownish crusts and with slight watery discharge and a few with raw areas. The patient is a known case of bronchial asthma. Histopathology of foot and face lesion shows inflammatory cell infiltrate predominantly comprising of eosinophils, small- and medium-sized blood vessels are thickened. P-antineutrophil cytoplasmic antibody positivity was seen. Thus, on the basis of positive findings which satisfy the criteria for eosinophilic granulomatosis with polyangiitis, we diagnosed this as a case of eosinophilic granulomatosis with polyangiitis, and for rarity of this case, we would like to report it.

Anogenital lichen sclerosus.

Lichen sclerosus (LS) was first described by Hallopeau in 1887. It is a chronic inflammatory condition most commonly involving the anogenital region with a relapsing course and a potential for destruction, functional impairment, atrophy, and malignant changes. LS affects both sexes with a female preponderance of 5:1. The exact prevalence of the disease is difficult to predict as the lesions are asymptomatic in the initial phase and later when the complications arise patients might visit the surgeon, pediatrician, gynecologist, or urologist. The etiology of LS has a complex interplay of genetic factors, autoimmunity, infections, and trauma. Physical examination to assess the extent of the disease and decide the line of management is the most crucial step in the management. Corticosteroids, calcineurin inhibitor, retinoids, phototherapy, and surgery can be helpful. Self-examination and long-term follow-up are necessary.

Topical corticosteroids in dermatology.

Since their introduction, topical corticosteroids have become indispensable in the treatment of various dermatoses. Hydrocortisone was the first compound. Modifications in the basic structure generated in vivo activity and thus different topically active compounds were discovered. Apart from the Stoughton vasoconstrictor assay, various other methods are used for potency assessment of topical corticosteroids. Topical corticosteroides are classified based upon potency and action of these molecules. Mechanism of action at the cellular level and indications of topical corticosteroid use have been discussed. Various adverse effects often occur as an extension of their activity combined with inappropriate usage. Tachyphylaxis and contact allergy are potential problems in clinical practice. Newer compounds with improved risk-benefit ratio are available.

Exogenous Ochronosis.

Exogenous ochronosis (EO) is a cutaneous disorder characterized by blue-black pigmentation resulting as a complication of long-term application of skin-lightening creams containing hydroquinone but may also occur due to topical contact with phenol or resorcinol in dark-skinned individuals. It can also occur following the use of systemic antimalarials such as quinine. EO is clinically and histologically similar to its endogenous counterpart viz., alkaptonuria, which, however, exhibits systemic effects and is an inherited disorder. Dermoscopy and in vivo skin reflectance confocal microscopy are noninvasive in vivo diagnostic tools. It is very difficult to treat EO, a cosmetically disfiguring and troubling disorder with disappointing treatment options.