Diagnosis: alopecia areata or not?

Alopecia areata is a common cause of hair loss in children and adults. In most cases, the diagnosis is straight forward and is easily made based on the patient's history and clinical presentation. However, in two specific scenarios, the diagnosis can be difficult and may require a scalp biopsy. We present four cases that illustrate these two problematic differentials: alopecia areata versus trichotillomania in adolescent females; and diffuse alopecia areata versus telogen effluvium versus androgenetic alopecia in adult women. Tables compare and contrast the clinical and histopathologic features of these nonscarring localized and diffuse alopecias.

Histopathology of an adverse reaction to a eutectic mixture of the local anesthetics lidocaine and prilocaine.

A unique histopathologic reaction to the topical application of a eutectic mixture of the local anesthetics lidocaine and prilocaine (EMLA), used for topical anesthesia prior to biopsy in two children is described. Standard application of EMLA cream under occlusion for 1 h was given to both patients. The biopsies in both cases demonstrate focal vacuolization of the upper spinous and granular layers. The epidermis was focally separated from the dermis in areas of basal vacuolar alteration. Electron microscopy performed in one case demonstrated the dermal-epidermal cleft to be secondary to alteration of the basal cells with condensation of the cytoplasm and cytologic degeneration similar to that seen in epidermolysis bullosa simplex.

Neutrophilic spongiosis in pemphigus.

BACKGROUND: Acantholysis is the histologic hallmark in the diagnosis of all forms of pemphigus. However, biopsy specimens of early lesions may lack acantholysis and show only eosinophils in the epidermis in areas of spongiosis (eosinophilic spongiosis). We report two cases of pemphigus foliaceus and two cases of unclassified pemphigus (foliaceus vs vulgaris) in which neutrophilic spongiosis was the prominent histologic finding. OBSERVATIONS: Four patients developed blistering skin disorders that spared the mucous membranes. Skin biopsy specimens in all four patients showed striking infiltration of neutrophils into the epidermis. Acantholysis was focal and was absent in some sections. Direct immunofluorescence demonstrated intercellular deposition of IgG and C3 within the epidermis in all cases. There was no IgA deposition. Gram's stains were negative for bacteria in three cases and revealed Gram-positive cocci overlying an eroded area in one case. However, the neutrophilic spongiosis in this case extended well beyond the area of impetiginization. CONCLUSIONS: The histologic differential diagnosis of neutrophils in the epidermis includes pustular psoriasis, subcorneal pustular dermatosis, intraepidermal neutrophilic IgA dermatosis, superficial IgA pemphigus, toxic shock syndrome, Sweet's syndrome, and superficial fungal and bacterial infections. We conclude that pemphigus be added to this differential diagnosis and recommend direct immunofluorescence when neutrophilic spongiosis is observed.

Nevoid malignant melanoma: morphologic patterns and immunohistochemical reactivity.

The term "nevoid malignant melanoma" (nevoid MM) is used here to describe rare nodular malignant melanomas that may escape detection in routine histological sections due to the lack of a prominent intraepidermal component, sharp lateral circumscription and evidence of partial maturation with descent in the dermis. Nevoid MM mimic ordinary compound or intradermal melanocytic nevi when the melanoma cells are small, or Spitz's nevi when the cells are large. The patterns of HMB-45 staining in 12 nevoid MM were compared with those in 107 melanocytic nevi. HMB-45 staining was strong in the dermal component of the nevoid MM, even in the absence of a junctional component. In common acquired and congenital nevi, the upper dermal component stained less than the junctional component of the lesion. The deepest components of these nevi were negative. Spitz nevi and cellular blue nevi had positive dermal cells, even without a junctional component. Additional staining for a proliferation marker, such as cyclin (PCNA) or Ki-67 (with the antibody MIB-1), can help further in distinguishing a nevoid MM from a Spitz's nevus. Melanoma has strong nuclear staining throughout the lesion. In contrast, Spitz's nevi have more staining at the top of the lesion than at the bottom. The patterns of HMB-45 and MIB-1 staining can be used along with standard histologic criteria for the diagnosis of nevoid MM. Clinicopathologic correlation is needed to distinguish some metastatic melanomas from primary nevoid MM.

Atypical melanocytic lesions in epidermolysis bullosa.

We report a 6-year-old female with recessive dystrophic epidermolysis bullosa (RDEB) who presented with a very large acquired melanocytic lesion. The lesion demonstrated many features both clinically and histologically that made the distinction from malignant melanoma difficult. The pathogenesis of this lesion and other unusual melanocytic lesions seen in the setting of acute and chronic blistering disorders seems related to repeated episodes of disruption of the dermal-epidermal junction.

Infantile generalized pustular psoriasis associated with lytic lesions of the bone.

Generalized pustular psoriasis is rare in children, especially in those less than 1 year of age. Lytic lesions of the bone have been reported in children with psoriasis, but are rare. We describe an infant with the clinical and histopathologic features of generalized pustular psoriasis that began in the first few weeks of life. In addition, this patient had sterile lytic lesions of the bone. Despite significant improvement in the bone lesions, his skin condition was resistant to therapy.

Inflammatory and papulosquamous disorders of the skin and eye.

We have discussed herein the dermatologic and ocular manifestations of several inflammatory diseases. Cooperation between ophthalmologists and dermatologists can significantly enhance patient care and comfort. It is hoped that this review will stimulate increased awareness of the prevalence of ocular findings in these diseases and encourage cooperation between these specialties for the benefit of our patients.

Cutaneous myelofibrosis.

Cutaneous extramedullary hematopoiesis is rare, usually occurring in neonates following intrauterine viral infections, hereditary spherocytosis, or the twin transfusion syndrome. Only 20 cases of cutaneous extramedullary hematopoiesis have been reported in adults, all with myelofibrosis. The cutaneous infiltrates may be atypical and difficult to distinguish from leukemia cutis. We have studied a 65-year-old woman with myelofibrosis and approximately 40 violaceous, firm, non-tender cutaneous nodules measuring 1 to 4 cm in diameter, located on her abdomen near a splenectomy scar. Histologically, the lesions had a dense infiltrate of myeloid cells in all stages of maturation, atypical large cells with multilobate nuclei or multiple nuclei, resembling atypical megakaryocytes, and fibroblasts. Although the patient received erythropoietin therapy prior to the development of the nodules, erythroid progenitors were not seen. Reticulin was increased particularly surrounding the atypical megakaryocytes. The myeloid cells stained for chloroacetate esterase and with the polyclonal antibody MAC 387. Atypical megakaryocytes stained for Factor XIIIa and Factor VIII-related antigen. Dendritic Factor XIIIa positive cells were also increased. The skin lesions remain unchanged grossly one year after their development.

Significant melanocytic lesions in infancy, childhood, and adolescence.

Malignant melanoma is diagnosed yearly in approximately 300 persons under age 20 in the United States. Relatively recent advances in dermatology include the recognition of lesions felt to be potential precursors of malignant melanoma. Small congenital melanocytic nevi, present in 1 per cent of all newborn infants, may have a small but definite potential for developing malignant melanoma. Furthermore, despite inconclusive data, many leading dermatologists now advocate removal of these small congenital lesions. Giant congenital melanocytic nevi, with their strong predilection for undergoing malignant change, are removed surgically at an early age, often in multistaged procedures. Dermabrasion, once felt to have a role in the treatment of giant congenital nevi, does not remove the malignant potential of these lesions. The dysplastic nevus syndrome, recognized in 1976, identifies individuals at increased risk for developing melanoma. Adolescents who have the dysplastic nevus syndrome or who are members of families with the syndrome require close medical supervision and patient education. The benign Spitz nevus, with its histologic similarity to malignant melanoma, continues to challenge the dermatopathologist and clinician. These lesions--the Spitz nevus, dysplastic nevus, congenital melanocytic nevus, and malignant melanoma--must all be actively considered when regarding the many other benign melanocytic lesions found in infancy, childhood, and adolescence.