Histopathology of the nail.

Patients are often very concerned about the diagnosis and treatment of an unsightly nail problem. Nail biopsy findings can enhance the accuracy of clinical diagnosis, just as skin biopsy is often crucial to the diagnosis of skin disease. In addition, nail biopsy may be necessary for the early detection of a malignant tumor. A skillfully performed adequate nail biopsy, handled and processed and interpreted properly, can be an important part of a dermatologist's armamentarium in providing excellent comprehensive patient care.

[A case of agnosia for streets and houses unaccompanied by prosopagnosia of familiar faces due to the right occipital lobe infarction].

We reported a patient who showed agnosia for streets and homes unaccompanied by prosopagnosia of familiar faces following infarction in the right occipital lobe. A 70-years-old right-handed man admitted to our department because of sudden development of visual impairment. He had left hemianopsia, left unilateral spatial neglect and slight visual memory disturbance but no other neurological abnormalities. His verbal memory was maintained intact. He was, however, unable to distinguish the sceneries of buildings and streets regardless of their familiarities and often got lost in the hospital. His topographical abilities in map-sketching and route-description were partially impaired depending upon the familiarity of targets; the disability was observed toward unfamiliar targets. His ability in facial recognition was also partially impaired depending upon the familiarity of persons. The patient was unable to distinguish faces of unfamiliar persons, such as nurses and doctors whom he met following stroke, whereas he was able to distinguish faces of familiar persons, such as his family and friends. The brain MRI demonstrated infarction in the right medial occipital lobe including parahippocampal gyrus, lingual gyrus and fusiform gyrus. In general, the manifestation of agnosia for streets and houses is associated with prosopagnosia. The present case, however, exhibited only the former in association with the partial manifestation of the latter. The fact suggests that those two are independent syndromes. The present case also showed a dissociation in the abilities of topographical and facial recognition according to the familiarity of targets. The process for the retrieval and reference of acquired information and that for the acquirement of new visual information may work in an independent manner.

Fibrous hamartoma of infancy.

Fibrous harmartoma of infancy is a benign soft tissue tumor that occurs in the first few years of life. Although the lesion is not distinctive clinically, it has a characteristic microscopic appearance. Only 12 cases of fibrous hamartoma of infancy have been reported in the dermatology literature.

Calciphylaxis mimicking skin lesions of connective tissue diseases.

Calciphylaxis is a rare condition found in patients with end-stage renal disease and secondary hyperparathyroidism. We describe two cases of prominent cutaneous manifestations of calciphylaxis in which skin lesions were refractory to topical treatments. We also include a brief description of calciphylaxis.

Dermatologic disorders of the foot.

This article includes a description of common problems of greatest interest to nondermatologist physicians who treat the foot. These include plantar warts, corns and callouses, toenail problems, and some common skin disorders, such as tinea pedis, pitted keratolysis, hyperkeratosis and fissures, and contact dermatitis. Certain neoplasms, including squamous cell carcinoma, verrucous carcinoma, and melanoma also are discussed.

An epidermal proliferative reaction associated with a silicone gel breast implant.

A variety of local and systemic adverse reactions has been attributed to silicone prostheses used for augmentation or reconstructive mammoplasty. We present a patient who developed an unusual local cutaneous reaction to a silicone breast implant, which was characterized clinically by macular erythema and focal ulceration and histologically by a basaloid proliferative epidermal reaction. The epidermal changes seen histologically simulated those overlying dermatofibromas and were felt to be reactive secondary to silicone leakage and fibrosis. The process resolved postexplantation of the prosthesis.

Clinical skin thickening following spinal cord injury studied by histopathology.

Dermatohistopathologic studies were performed in persons with spinal cord injury to evaluate the clinical observation of skin thickening. Twenty subjects were included in a prospective acute study and 59 subjects in a chronic study. Skin biopsies of the lower lateral thigh were studied by routine histopathology. The most common histopathologic findings included dermal fibrosis and perivascular inflammatory infiltrate. Dermal fibrosis was already identified within two months after injury in the acute study. In chronic patients, dermal fibrosis was found in 65 percent of persons with tetraplegia compared to 25 percent with paraplegia (p = .0038). Perivascular inflammatory infiltrate was less frequent and its presence was not associated with the level of injury. Histopathologic findings were generally not as prominent as the clinical picture. This disparity may be explained by a combination of edema and dermal fibrosis. Loss of autonomic nervous system control or other neuroendocrine dysfunction is suspected as a causative factor in the pathogenesis of these findings.

Noninflammatory bullae associated with epsilon-aminocaproic acid infusion.

Three patients who had cardiac surgery developed a transient, noninflammatory subepidermal bullous eruption on the legs after epsilon-aminocaproic acid infusion. Fibrin thrombi were demonstrated in papillary dermal vessels. The use of epsilon-aminocaproic acid as an antifibrinolytic agent may predispose patients to cutaneous vascular thromboses.

Clinical and histologic features of primary oxalosis.

Primary oxalosis should be considered in patients with multisystem disease of the kidneys, heart, peripheral vasculature, and skin. Crystalline deposits can lead to nephrolithiasis with kidney failure, complete heart block, peripheral vasospasm, and livedo reticularis, as in our patient. Crystals were first observed in the myocardial biopsy specimen and then identified as calcium oxalate in skin from an area of livedo reticularis.

Recurrent and metastatic cutaneous neuroendocrine (Merkel cell) carcinoma mimicking angiosarcoma.

An elderly man presented with bright red-to-purple confluent nodules and plaques of the scalp that appeared clinically consistent with angiosarcoma. He had undergone surgical removal of a similar lesion from his left temple seven months before this presentation. Although routine histologic examination was not sufficient for diagnosis, Merkel cell carcinoma was diagnosed by immunohistochemical studies and electron microscopy. In addition, oat cell carcinoma of the lung was excluded with a computed tomographic scan of his chest. With chemotherapy, the recurrent and metastatic lesions of Merkel cell carcinoma completely resolved, rapidly recurred, and resolved a second time with chemotherapy. Eight months following the fourth course of chemotherapy, the patient again developed widespread cutaneous lesions. He committed suicide within one month of this last recurrence. An autopsy revealed no primary tumor other than of the skin.

Histologic variation in the skin lesions of the glucagonoma syndrome.

Three cases of glucagonoma syndrome were seen in 1 year. Study of the skin biopsies from the first two cases led to a correct diagnosis from skin biopsy of the third case, although it was not suggested clinically. In each case serum glucagon levels were high and a pancreatic tumor was found, with complete remission of symptoms in cases 1 and 3 after resection; case 2 refused surgery and has died. A total of nine skin biopsies from the three patients showed a variety of findings: epidermal necrosis; subcorneal pustules, either isolated or associated with necrosis of the epidermis; confluent parakeratosis, epidermal hyperplasia, and marked papillary dermal angioplasia; and suppurative folliculitis. The clinical lesions in this syndrome vary from bright red macules to annular superficial erosions and flaccid pustules. Similarly, several histopathologic features of the disease can occur, which may represent the progression of the disease. No single histologic feature was specific for the disease, but a combination of the features is probably diagnostic. Therefore, multiple skin biopsies are recommended when this diagnosis is suspected.

Histopathology of the nail.

Introductory sections on why and how to biopsy the nail unit and on the handling and processing of the specimen are followed by a presentation of normal histologic findings. These are contrasted with the abnormal changes in infections, especially fungal, of the nail unit, and in skin diseases that may affect the nail, especially psoriasis and lichen planus. Benign and malignant neoplasms that may occur beneath or around the nail, including melanoma, conclude the discussion.

Herpes gestationis. Persistent disease activity 11 years post partum.

A patient had herpes gestationis that had persisted for over 11 years post partum despite aggressive therapy with corticosteroids, dapsone, and various immunosuppressants. Postpartum exacerbation is a characteristic feature of herpes gestationis. However, it usually is of short duration and is responsive to conventional therapy.

Recurrent Spitz's nevus.

A recurrence of a spindle- and epithelioid-cell nevus following partial removal is described. Clinical and histologic photographs of the original and recurrent lesion and an immunohistochemical stain (S-100) which highlights melanocytic cells and their pattern of growth are included. This nodular recurrence of a Spitz's nevus is contrasted with macular recurrence of ordinary melanocytic nevi that may follow partial removal by shaves. It is presented in order to promote recognition and prevent misdiagnosis of such a recurrence as a malignant melanoma.