Kiran Motaparthi

Infectious Diseases: Bacterial Infections

The focus of this chapter is cutaneous infections due to bacteria, Leishmania, and fungi, and the available evidence supporting specific treatments, both medical and surgical, for these conditions in children and adolescents. For some infections, adjunctive therapies are recommended in addition to first-line, second-line, and third-line treatments.

Infectious Diseases: Leishmaniasis

The focus of this chapter is cutaneous infections due to Leishmania and the available evidence supporting specific treatments, both medical and surgical, for these conditions in children and adolescents. For some infections, adjunctive therapies are recommended in addition to first-line, second-line, and third-line treatments.

Palisaded neutrophilic granulomatous dermatitis: Spectrum of histologic findings in a single patient

GA: granuloma annulare PNGD: palisaded neutrophilic granulomatous dermatitis RA: rheumatoid arthritis INTRODUCTION Palisaded neutrophilic granulomatous dermatitis (PNGD) is a typically associated with underlying disease states, including autoimmune connective tissue disease, lymphoproliferative disorders, and infections. Although most common in patients with rheumatoid arthritis (RA), PNGD can also be seen in patients with systemic lupus erythematosus and systemic vasculitides. Clinically, PNGD presents with tender, erythematous-to-violaceous papules, plaques, or nodules affecting the extensor surfaces. Acral, including palmar, involvement is characteristic, and umbilicated papules overlying bony prominences are also described. Histologically, early lesions of PNGD present with neutrophilic infiltrates and leukocytoclastic vasculitis; fully developed lesions feature palisaded granulomas with collagen trapping and neutrophil remnants. Given the wide range of clinical features, histopathologic findings, and underlying systemic diseases, the diagnosis of PNGD can be challenging, requires careful clinicopathologic correlation, and relies on knowledge of the varying histologic findings. Here, PNGD with underlying RA in a single patient with 3 distinct histopathologic patterns is presented.

Collagenous and elastotic marginal plaques of the hand: a potential clue to the diagnosis of alkaptonuria.

Collagenous and elastotic marginal plaques of the hand (CEMPH) is a rare, chronic keratoderma characterized by hyperkeratotic linear plaques located along the radial and ulnar aspects of the hands bilaterally. As an isolated finding, CEMPH occurs secondarily to chronic trauma and photodamage. Herein, CEMPH is described as a manifestation of alkaptonuria (AKU). In addition to keloidal collagen, ochronotic fibers and fragmented, thickened elastic fibers were observed. Additionally, mucin deposition—not previously described in this clinical context—was also identified. Given their overlapping clinicopathologic features, CEMPH due to AKU should be distinguished from the acquired variant as well as acrokeratoelastoidosis.

Erythrodermic psoriasis after discontinuation of ixekizumab

INTRODUCTION Erythroderma is defined as generalized redness and scaling affecting more than 90% of the skin surface and often accompanied by systemic complications such as hypothermia, dehydration, and electrolyte imbalance. Treatment is targeted at the underlying cause, and preexisting dermatoses are identified in 65% of patients. Psoriasis is the most common underlying disease in erythrodermic adults, accounting for almost half of cases, and can be triggered by withdrawal of medications, infection, or irritant contact dermatitis.

Paraneoplastic pemphigus mimicking toxic epidermal necrolysis: An underdiagnosed entity?

CLL: chronic lymphocytic leukemia DSG: desmoglein ELISA: enzyme-linked immunosorbent assay EP: envoplakin PNP: paraneoplastic pemphigus IIF: indirect immunofluorescence PP: periplakin SJS: Stevens-Johnson syndrome TEN: toxic epidermal necrolysis INTRODUCTION Paraneoplastic pemphigus (PNP) is an autoimmune blistering syndrome with 5 well-described clinicopathologic phenotypes. Nguyen et al categorized these subtypes as pemphigus-like, pemphigoid-like, erythema multiforme-like, graftvs-host-diseaseelike, and lichen planuselike. However, there is increasing recognition of PNP simulating Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). Herein, we propose SJS/TEN-like PNP as a distinct subtype of PNP. We present 2 new cases of SJS/TEN-like PNP and review the previously reported cases of this subtype. Clinicopathologic factors that merit consideration for PNP in this context include a history of associated underlying neoplasia, the absence of a new drug, and histopathology indicative of chronicity or acantholysis. In patients with these features and clinical morphology typical of SJS/TEN, serologic evaluation for IgG autoantibodies against envoplakin (EP), desmoglein (DSG) 1, and DSG3 should be considered in order to exclude SJS/TEN-like PNP.

Prurigo pigmentosa: Case series and differentiation from confluent and reticulated papillomatosis

CARP: confluent and reticulated papillomatosis PP: prurigo pigmentosa INTRODUCTION Prurigo pigmentosa (PP) is an uncommon, acquired inflammatory disorder with a predilection for young adults of Asian descent. This condition is manifested by highly pruritic, reticulated, and erythematous papules that resolve with hyperpigmentation. Multiple cases of PP have been reported since its initial description in 1971 by Nagashima et al; however, this dermatosis is still underdiagnosed or misdiagnosed. The most significant challenge limiting the identification of PP is successful distinction from confluent and reticulated papillomatosis (CARP). Herein, 2 patientswith PP are described, with a focus on differentiating features from CARP.

Eccrine hamartoma with spectrum of histologic findings associated with limb deformity

A 12-year-old male with no significant past medical history presented for evaluation of a solitary painful plaque located on his right medial plantar foot. The lesion was first noticed approximately 3 years prior after mild trauma sustained while falling off his bicycle. Following this trauma, a brown hyperpigmented patch formed (Fig. 1), and the patient began to notice progressive pain and difficulty with ambulation. Subsequent compensatory supination of the right foot ensued and has since manifested in gross size discrepancy between the right and left foot. Initial treatment with casting, boots, and hydrocortisone resulted in no improvement of the patient’s symptoms.

Rapamycin for refractory discoid lupus erythematosus

Generalized discoid lupus erythematosus can pose a therapeutic challenge for dermatologists. Current treatment emphasizes photoprotection, topical and systemic steroids, and steroid‐sparing immunosuppressive agents if necessary. Rapamycin, also known as sirolimus, selectively inhibits mammalian target of rapamycin, a regulatory kinase responsible for multiple signal transduction pathways. Mammalian target of rapamycin inhibition reduces cell division, lymphocyte proliferation, cytokine release, and downstream pathways unique from other classes of immunomodulatory drugs. Herein, we present a case of generalized discoid lupus erythematosus resistant to topical steroids, prednisone, azathioprine, mycophenolate mofetil, hydroxychloroquine, and thalidomide. The addition of rapamycin led to a positive treatment response within 6 weeks, with good tolerance of the medication and no adverse effects. The current literature supporting the use of rapamycin in the treatment of autoimmune connective tissue diseases is also briefly reviewed. For patients with severe or generalized discoid lupus erythematosus refractory to conventional treatment, rapamycin may be a useful therapeutic consideration.

Cyclosporine for corticosteroid-refractory acute generalized exanthematous pustulosis due to hydroxychloroquine

Acute generalized exanthematous pustulosis most often manifests 1–2 days following exposure to a characteristic drug, such as aminopenicillins, calcium‐channel blockers, or terbinafine. Recovery is usually rapid following drug withdrawal, and systemic corticosteroids represent the historic treatment of choice. Herein, acute generalized exanthematous pustulosis incited by hydroxychloroquine is briefly reviewed: a prolonged latency and recalcitrance to corticosteroids are noteworthy. In this unique context, cyclosporine tapered over several months is an effective therapeutic option.