What Your Dermatopathologist Wants You to Know.

The skin biopsy and histologic examination are an important part of providing dermatologic care. Effective communication with your dermatopathologist on the biopsy requisition form helps provide clinicopathological correlation and facilitates accurate and timely histopathologic diagnosis of the biopsy.

Direct Immunofluorescence.

Direct immunofluorescence (DIF) is a valuable diagnostic tool in the dermatology clinic. The proper use of a biopsy for DIF is dependent on several factors, including appropriate clinical indication, correct clinical site selection, and proper specimen handling and transport. Improper use of DIF can lead to false negatives, decreased diagnostic yield, and poor resource utilization. This article provides instruction on the appropriate indications and biopsy site selection for DIF. Three examples of skin diseases in which DIF would be particular useful when making a diagnosis are provided.

Pemphigoid gestationis.

We present a 21-year-old primigravida woman with a several-week history of pruritic, edematous, targetoid plaques that appeared initially on the abdomen, flanks, and legs and that progressed to involve the inner aspects of the upper arms and lateral aspects of the chest. The histopathologic findings showed perivascular and interstitial dermatitis with eosinophils and vacuolar changes with linear C3 deposition at the basement-membrane zone on direct immunofluorescence study. A diagnosis of pemphigoid gestationis was made. Pemphigoid gestationis is a rare, bullous dermatosis of pregnancy that may be associated with prematurity and small-for-gestational age birth weights. The diagnosis is often made with direct immunofluorescence studies of perilesional skin. Oral glucocorticoids remain the gold standard of therapy in moderate-to-severe cases. The edematous papules and plaques of pemphigoid gestationis may be particularly difficult to distinguish from polymorphic eruption of pregnancy; therefore, immunofluorescence studies are prudent. Prompt recognition and appropriate management may reduce morbidity of this disease, which often recurs with subsequent pregnancies.

Scleredema diabeticorum.

We present a case of scleredema with a leonine facies in a 56-year-old man with a history of poorly controlled diabetes mellitus. The patient initially presented with erythematous, edematous papules and plaques on the face, neck, and upper back.

Minocycline-induced hyperpigmentation in multibacillary leprosy.

Minocycline has been used in the treatment of leprosy since the demonstration of its efficacy in inhibiting Mycobacterium leprae growth in 1987. Hyperpigmentation, a well-documented adverse effect, classically shows 3 clinical and histological patterns: type I consists of blue-black pigmentation in areas of current or previous inflammation, type II consists of blue-gray pigmentation of normal skin, often seen on the legs, and type III consists of diffuse muddy-brown pigmentation accentuated on sun-exposed sites. Whereas type I hyperpigmentation stains positively for hemosiderin and type III hyperpigmentation stains positively for melanin, type II hyperpigmentation stains positively for both. We describe 2 patients with leprosy on minocycline therapy who developed multiple patches of blue-gray pigmentation within preexisting leprosy lesions. Biopsies from both patients demonstrated deposition of brownish-black pigment granules within the cytoplasm of foamy histiocytes that was highlighted by both Perls and Fontana-Masson stains. Given the clinical and histological findings in our patients, it is as yet unclear whether this coexistent type I clinical pattern and type II histopathologic pattern of pigmentation is unique to multibacillary leprosy. These findings provide support for the existence of additional subtypes of minocycline-induced hyperpigmentation that do not adhere to the classic 3-type model described.

Alefacept therapy for nephrogenic systemic fibrosis: a case series.

Nephrogenic systemic fibrosis (NSF) is a recently described systemic fibrosing disorder that develops in the setting of renal insufficiency. Exposure to gadolinium has been implicated in its development. While the primary manifestations are cutaneous, systemic fibrosis can also occur. Several anecdotal reports of successful treatment have been reported, but there is no consistently efficacious therapy. We report the improvement or stabilization of cutaneous disease in three patients with NSF using alefacept therapy.

Alefacept for moderate to severe atopic dermatitis: a pilot study in adults.

BACKGROUND: Atopic dermatitis is a common inflammatory skin condition with acute and chronic phases showing a prevalence of memory T cells. Alefacept is a fully human LFA-3/IgG1 fusion protein that inhibits T-cell activation and selectively reduces memory T cells, which may prove to be effective in the treatment of atopic dermatitis. OBJECTIVE: We sought to evaluate clinical response of alefacept intramuscular (IM) injection for 16 weeks in adults with atopic dermatitis. METHODS: This was an open-label study of a 16-week treatment regimen of alefacept IM injection in adults with moderate to severe inflammatory atopic dermatitis. Patients received alefacept (30 mg IM) weekly for the first 8 weeks. At week 9, patients who did not achieve a 50% reduction in their Eczema Area Severity Index (EASI) score continued on alefacept (30 mg IM) weekly; those patients with a 50% reduction in their EASI (EASI 50) score or higher had their weekly dose decreased (15 mg IM) for the remaining 8 weeks. RESULTS: Nine patients with moderate to severe atopic dermatitis were enrolled and treated. At the primary end point, week 18, 1 patient achieved EASI 50 score and 1 patient achieved EASI 90 score; 4 patients had a decrease in EASI score of less than 50%, 1 patient had an increase in EASI score, and 2 patients withdrew early before the primary end point because of worsening disease. A Physician Global Assessment score of mild was achieved in 2 patients and 1 patient achieved a Physician Global Assessment score of almost clear. Minimal pruritus was reported by 3 patients and 1 patient reported no pruritus. The 16-week course of alefacept was well tolerated. LIMITATIONS: The study was inherently limited by its small sample size, concomitant use of antihistamines, and open-label design, which increases the likelihood of observer and self-assessment bias. CONCLUSION: The treatment regimen of alefacept for 16 weeks was well tolerated by our patients. Although, in this study, only 2 of the 9 patients with atopic dermatitis responded to treatment with alefacept, the study was inherently limited by the small sample size. Additional studies with a larger sample size, continued weekly use, or concomitant use of ultraviolet-B light therapy may be warranted to evaluate the possibility of alefacept as a therapy for patients with chronic atopic dermatitis.

Combination immunosuppressive therapies: the promise and the peril.

BACKGROUND: Targeted immunotherapeutic agents (TIs), also known as biological agents, are efficacious treatments for many immunologically mediated disorders, including psoriasis. In several of these diseases, including rheumatoid arthritis, Crohn's disease, and multiple sclerosis, certain TIs have been studied in combination with nonspecific immunosuppressive agents and with other TIs. OBSERVATIONS: Recently, the rheumatology, neurology, and gastroenterology literature has reported several examples of possible associated toxic effects when certain TIs are used in combination with other immunosuppressive agents. These toxic effects have included an increased risk of infection and malignancy. CONCLUSIONS: Combination therapies are often used by dermatologists. Several TIs have been approved for psoriasis; however, clinical trials using these drugs in combination with other immunosuppressive agents have not yet been performed. The implications for dermatologists of the toxic effects associated with TI combination therapy are unclear. However, combination therapy with certain TIs should be used with caution until more data are available.