Urticaria multiforme in an adolescent: A rare benign rash not to be ignored.

Urticaria multiforme, first described in 1997, also called acute ring urticaria, is a clinical variant of acute urticaria. We relate the case of a 16-year-old adolescent with an extensive pruritic eruption of erythematous annular lesions of variable shapes, arciform, or polycyclic with an ecchymotic center. Urticaria multiforme is described in children aged from 4 months to 4 years, rarely in adolescents. As far as we know, this is the 4th case reported in the literature.

Adenomatoid tumor of the skin: Differential diagnosis of an umbilical erythematous plaque.

Adenomatoid tumors are benign tumors of mesothelial origin that are usually encountered in the genital tract. Although they have been observed in other organs, the skin appears to be a very rare location, with only one case reported in the literature to our knowledge. We report a second case of an adenomatoid tumor, arising in the umbilicus of a 44-year-old woman. The patient presented with an 8-month-old erythematous and firm plaque under the umbilicus. A skin biopsy showed numerous microcystic spaces dissecting a fibrous stroma and lined by flattened to cuboidal cells with focal intraluminal papillary formation. This little-known diagnosis constitutes a diagnostic pitfall for dermatopathologists and dermatologists, and could be misdiagnosed as other benign or malignant entities. Through this case report, a practical approach and diagnostic keys have been devised to avoid misdiagnosis and overtreatment.

Erythema Nodosum Leprosum-Like Lesions Are a Histopathologic Pattern in Whipple's Disease and a Sign of the Immune Reconstitution Inflammatory Syndrome: A Case Series and Review of the Literature.

Inflammatory and subcutaneous nodules can arise in treated and untreated cases of Whipple disease (WD). The inflammatory immune reconstitution syndrome describes paradoxical clinical inflammatory worsening of a preexisting condition because of a return of immune function. Clinicopathologic examination of 4 patients with WD who presented with erythema nodosum leprosum (ENL)-like lesions and the findings of a systematic review of this phenomenon revealed that ENL-like lesions occurred in predominantly middle-aged male patients who suffered from WD, mostly on the legs. Patients showed a nonvasculitic, mostly septal panniculits with neutrophils, macrophages, and lymphocytes. Numerous bacteria-laden periodic acid-Schiff + macrophages and free bacilli were detected in the dermis, as well as subcutaneous septae and adipose lobules. These lesions occurred in both untreated and treated patients as part of inflammatory immune reconstitution syndrome. In conclusion, ENL-like lesions represent a characteristic histopathologic pattern associated with WD, which can occur in different contexts whenever there is a change in the immunological status of the patient. This change can be triggered by antimicrobial treatment, immunomodulatory and immunosuppressant therapy, or occur spontaneously, rarely.

Nail pathology.

When dealing with nails, pathologic examination is often indispensable to reach an accurate diagnosis. This requires a biopsy correctly performed by the dermatologist, a specimen correctly handled in the pathology lab, and a pathologist with good knowledge of the various nail conditions. The normal nail histology is first described in this paper. The pathologic aspects of melanocytic lesions, nonmelanocytic tumors of the nail apparatus, inflammatory nail conditions, and onychomycosis are then considered, together with their main differential diagnoses.

A retrospective study of squamous cell carcinoma of the nail unit diagnosed in a Belgian general hospital over a 15-year period.

BACKGROUND: Squamous cell carcinoma (SCC) is the most common malignant tumor at the nail unit. It mainly affects middle-aged men, with a peak incidence between 50 and 69 years of age. Diagnosis is often delayed because of the slow evolution of the lesion and multiple clinical features. OBJECTIVE: We sought to characterize the different clinical and histopathological patterns of SCC of the nail unit and evaluate their therapeutic outcome. METHODS: Records for 58 patients were retrieved from our department's dermatopathology database over a period of 15 years (1995-2011) and the patients recontacted. RESULTS: Of the 58 patients, 51 were eligible for follow-up. There was a male predominance (72.5%). The fingers were most commonly affected (98%), the right index and long fingers being most commonly affected (20.8% each). The nail bed was mainly affected. The commonest clinical signs were, in decreasing order, subungual hyperkeratosis, onycholysis, oozing, and nail plate destruction. The majority of SCC of the nail unit was in situ (63%). The recurrence rate of all treatments taken together was 30.6%. LIMITATIONS: Retrospective study design is a limitation. CONCLUSIONS: SCC of the nail unit mostly affects men aged 50 to 69 years. Most cases were the warty type, with oozing being an underrecognized clinical sign. Contrary to prior studies, most lesions were in situ, and bone involvement was uncommon. Conservative surgical resection should be the first-line treatment when the bone is not involved. Recurrence rate is high when a procedure other than Mohs micrographic surgery is performed.

Tangential excision of pigmented nail matrix lesions responsible for longitudinal melanonychia: evaluation of the technique on a series of 30 patients.

OBJECTIVES: We sought to assess the shave biopsy technique, which is a new surgical procedure for complete removal of longitudinal melanonychia. We evaluated the quality of the specimen submitted for pathological examination, assessed the postoperative outcome, and ascertained its indication between the other types of matrix biopsies. DESIGN: This was a retrospective study performed at the dermatologic departments of the Universities of Liège and Brussels, Belgium, of 30 patients with longitudinal or total melanonychia. RESULTS: Pathological diagnosis was made in all cases; 23 patients were followed up during a period of 6 to 40 months. Seventeen patients had no postoperative nail plate dystrophy (74%) but 16 patients had recurrence of pigmentation (70%). LIMITATIONS: This was a retrospective study. CONCLUSIONS: Shave biopsy is an effective technique for dealing with nail matrix lesions that cause longitudinal melanonychia over 4 mm wide. Recurrence of pigmentation is the main drawback of the procedure.

Immunohistochemical study of 40 cases of longitudinal melanonychia.

The etiology of longitudinal melanonychia (LM) is difficult to establish by clinical and dermoscopic examinations alone. Microscopic examination of the nail matrix remains crucial. Two groups of LM may be identified: melanocytic activation (melanic pigmentation of the matrix epithelium without any increase in the density of melanocytes) and melanocytic proliferation (lentigo, nevus, or melanoma). The histological examination is challenging, and immunohistochemical investigations can be helpful. The objective of this study was to analyze the immunohistochemical findings with routinely used markers in melanocytic tumors-S-100 protein, HMB-45, and Melan-A-in LM. A series of 40 cases were analyzed: 10 activations, 4 lentigines, 7 nevi, 12 in situ melanomas, and 7 invasive melanomas. The sensitivity of S-100 protein is weak in benign and malignant intraepithelial melanocytes of the nail matrix, and if this marker is performed alone, it may be wrongly reassuring. However, the use of S-100 protein is essential to differentiate invasive melanoma, lacking an intraepithelial component, and particularly desmoplastic melanoma, from epithelial and mesenchymal tumors. HMB-45 and Melan-A are more sensitive than S-100 protein for the evaluation of intraepithelial melanocytic proliferation of the nail apparatus, with HMB-45 being the most intense marker. In the dermal component, HMB-45 and Melan-A were less sensitive than S-100 protein. In conclusion, we recommend that the panel of antibodies used for histological evaluation of LM should include HMB-45 and/or Melan-A and S-100 protein only if an invasive melanoma is suspected.

Cryopyrin-associated periodic syndrome: an autoinflammatory disease manifested as neutrophilic urticarial dermatosis with additional perieccrine involvement.

A female newborn presented with a congenital urticarial rash that consisted of fluctuating well-demarcated pink or pale reddish macules or slightly raised papules and plaques. In addition, purulent cerebrospinal fluid was present in the absence of evidence of congenital infection. Skin biopsy revealed a sparse infiltrate throughout the entire dermis, including the eccrine adventitia. The infiltrate was composed mostly of neutrophils, but rarely lymphocytes and eosinophils could also be seen. No vasculitis was present. Because of the presenting attributes, a diagnosis of cryopyrin-associated periodic syndrome (CAPS) was considered and the neonatal-onset multisystem inflammatory disorder (NOMID) that represents the most severe expression of the CAPS clinical spectrum was favored. Diagnosis was confirmed by identification of a mutation in the cold-induced autoinflammatory syndrome-1 gene and by an observed response to treatment with the interleukin-1 receptor antagonist anakinra. Both the clinical and histopathological findings of the presented case may represent a distinct entity within the spectrum of aseptic neutrophilic dermatitis. We refer to this spectrum as neutrophilic urticarial dermatosis (NUD), which may serve as a cutaneous marker of autoinflammation. NUD with perieccrine involvement should prompt consideration of CAPS, especially NOMID, in the context of neonatal multisystem disease.

[Retiform haemangioendothelioma: a case report]. / Hémangioendothéliome rétiforme : à propos d'un cas.

Retiform haemangioendothelioma is a locally aggressive, very rarely metastasizing vascular lesion. Histologically, it is characterized by distinctive arborizing blood vessels resembling "rete testis" and lined by endothelial cells with characteristic hobnail morphology. We present an additional case, in the leg of a 64-year-old patient. We discuss the classification of hemangioendotheliomas. The term hemangioendothelioma should be restricted to vascular tumours of "intermediate malignancy" but has been used to designate tumours with variable histological features and clinical behaviour. Spindle cell hemangio(endothelio)ma is currently regarded as a benign reactive lesion. Kaposiform hemangioendothelioma is potentially lethal due to consumption coagulopathy but no metastasizing case has been reported. Epithelioid hemangioendothelioma is associated with a significant metastatic risk and has been included in the category of malignant vascular tumors. The vascular lesions fulfilling the strict definition of hemangioendothelioma include retiform hemangioendothelioma, papillary intralymphatic angioendothelioma "Dabska's tumor", composite hemangioendothelioma and perhaps the controversial polymorphic hemangioendothelioma.

Acantholytic tumor of the nail: acantholytic dyskeratotic acanthoma.

Acantholytic dyskeratotic acanthomas of the skin have been recently described in several publications. They differ from acantholytic acanthomas by the presence of dyskeratosis. However these tumors have never been described in nails. We report three cases localized on the thumb nail.

Congenital disseminated juvenile xanthogranuloma with unusual skin presentation and renal involvement.

We present a case of congenital juvenile xanthogranuloma (JXG) with both cutaneous and renal involvement. Skin lesions consisted of bluish papules and nodules (blueberry muffin baby) located on the head, trunk and proximal extremities. Subsequent investigations revealed a renal mass. Histopathology of both cutaneous and renal specimens was consistent with JXG. Both clinical presentation and extracutaneous localization were remarkable.

New tools in nail disorders.

Tumors of the nail unit may be difficult to diagnose because of the screening effect of the nail plate. In longitudinal melanonychia, several new promising techniques assist with early diagnosis of melanoma (in vivo matrix dermoscopy and immunohistochemistry) as well as sparing as much of the healthy tissues as is possible (shave biopsy technique). Diagnosing nail disorders is in some instances difficult both for the clinician and the pathologist. New tools such as polymerase chain reaction have been proposed for onychomycosis, which accounts for more than half of nail conditions, will allow quick and accurate diagnosis. However, polymerase chain reaction analysis remains expensive and is not routinely used by clinicians. Scoring nail dystrophy by clinical observation remains very subjective; therefore, severity indexes have been proposed. Another emerging noninvasive technique is forensic analysis of nail clippings for detection of drug intake and abuse, as well as exposure to environmental pollution.

Intracellular activity of antibiotics in a model of human THP-1 macrophages infected by a Staphylococcus aureus small-colony variant strain isolated from a cystic fibrosis patient: pharmacodynamic evaluation and comparison with isogenic normal-phenotype and revertant strains.

Small-colony variant (SCV) strains of Staphylococcus aureus show reduced antibiotic susceptibility and intracellular persistence, potentially explaining therapeutic failures. The activities of oxacillin, fusidic acid, clindamycin, gentamicin, rifampin, vancomycin, linezolid, quinupristin-dalfopristin, daptomycin, tigecycline, moxifloxacin, telavancin, and oritavancin have been examined in THP-1 macrophages infected by a stable thymidine-dependent SCV strain in comparison with normal-phenotype and revertant isogenic strains isolated from the same cystic fibrosis patient. The SCV strain grew slowly extracellularly and intracellularly (1- and 0.2-log CFU increase in 24 h, respectively). In confocal and electron microscopy, SCV and the normal-phenotype bacteria remain confined in acid vacuoles. All antibiotics tested, except tigecycline, caused a net reduction in bacterial counts that was both time and concentration dependent. At an extracellular concentration corresponding to the maximum concentration in human serum (total drug), oritavancin caused a 2-log CFU reduction at 24 h; rifampin, moxifloxacin, and quinupristin-dalfopristin caused a similar reduction at 72 h; and all other antibiotics had only a static effect at 24 h and a 1-log CFU reduction at 72 h. In concentration dependence experiments, response to oritavancin was bimodal (two successive plateaus of -0.4 and -3.1 log CFU); tigecycline, moxifloxacin, and rifampin showed maximal effects of -1.1 to -1.7 log CFU; and the other antibiotics produced results of -0.6 log CFU or less. Addition of thymidine restored intracellular growth of the SCV strain but did not modify the activity of antibiotics (except quinupristin-dalfopristin). All drugs (except tigecycline and oritavancin) showed higher intracellular activity against normal or revertant phenotypes than against SCV strains. The data may help rationalizing the design of further studies with intracellular SCV strains.

Superficial acral fibromyxoma: clinical and pathological features.

Superficial acral fibromyxoma (SAFM) is a recently recognized myxoid tumor that usually occurs on the fingers and toes of middle-aged adults. We report on the typical case of a 50-year-old woman with a SAFM in the right big toenail that had been slowly growing for more than 10 years. To our knowledge, this case is the first reported case for which clinical pictures are available. Histologically, the lesion was non-encapsulated and was composed of stellate and spindle cells, arranged in a myxoid matrix. No atypia or mitotic figures were found. Neoplastic cells showed positive staining for CD34 and negative staining for epithelial membrane antigen (EMA), actin, desmin, keratins, S100 protein, CD99, and HMB45. Differential diagnosis encompasses benign and malignant myxoid and spindle cells tumors such as myxoid neurofibroma, sclerosing perineurioma, superficial angiomyxoma, and several low-grade myxoid sarcomas.

POEMS syndrome revealed by multiple glomeruloid angiomas.

POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, skin disorders) is a rare multisystemic disease associated with plasma cell dyscrasia. A 68-year-old woman with chronic renal insufficiency and arterial hypertension included in her medical history was admitted to the hospital with confusion, somnolence and asthenia. She presented ascites, hepatosplenomegaly, leg oedema, distal dysesthesias, leuconychia and multiple nodular purple red angiomas on the trunk, upper limbs and fingers. Hypothyroidism was revealed in the laboratory investigations and monoclonal IgG peak in immunoelectrophoresis. Electromyography showed both demyelinisating and axonal degenerative neuropathy. The diagnosis of POEMS syndrome was based on the dermatopathological examination of a cutaneous angioma; histology revealed features of glomeruloid angioma, a specific marker of this syndrome.

Cutaneous Mycobacterium chelonae infection extending distally in a hemodialysed patient.

We report a case of a cutaneous Mycobacterium chelonae infection on the dorsum of the forearm of a patient undergoing chronic hemodialysis. The infection showed a linear and distal extension. This unusual distal dissemination was apparently secondary to a venous reflux, a circulatory repercussion of the patient's arteriovenous fistula.