Annular Erythematous Eruption in a Pediatric Patient.

An 11-year-old girl presented in autumn with an asymptomatic rash on her arms, face, and legs of a 3-week duration. What is your diagnosis?

Dermatopathologic features of cutaneous squamous cell carcinoma and actinic keratosis: Consensus criteria and proposed reporting guidelines.

BACKGROUND: There is considerable variation in the literature regarding the dermatopathologic diagnostic features of and reporting guidelines for actinic keratosis (AK) and cutaneous squamous cell carcinoma (cSCC). OBJECTIVE: To develop consensus recommendations regarding diagnostic criteria, nomenclature, and reporting of AK and cSCC. METHODS: Literature review and cross-sectional multiround Delphi process including an international group of expert dermatopathologists followed by a consensus meeting. RESULTS: Consensus was achieved regarding the key dermatopathologic features necessary for diagnosing cSCC, AK, and associated variants; grading of degree of cellular differentiation in cSCC; utility of immunohistochemistry for diagnosis of cSCC; and pathologic features that should be reported for cSCC and AK. LIMITATIONS: Consensus was not achieved on all questions considered. CONCLUSION: Despite the lack of clarity in the literature, there is consensus among expert dermatopathologists regarding diagnostic criteria and appropriate reporting of AK and cSCC. Widespread implementation of these consensus recommendations may improve communication between dermatopathologists and clinicians, facilitating appropriate treatment of AK and cSCC.

Mycobacterium mucogenicum infection following dacryocystorhinostomy and Crawford tube placement.

IMPORTANCE: Nontuberculous mycobacterial infections of the skin can be seen in cases of immunosuppression and/or traumatic implantation of contaminated objects. Surgical settings with appropriate sterilization techniques have been immune to these types of infections. We report a case of nosocomially derived infection from a sterile procedure. OBSERVATIONS: A woman in her 70s presented with a facial lesion after an ophthalmologic procedure that was discovered to be a nontuberculous mycobacterial infection. It was successfully treated with oral antibiotics. CONCLUSIONS AND RELEVANCE: Nontuberculous mycobacterial infections should be considered in the differential diagnosis of new lesions arising after invasive procedures, even in immunocompetent patients in seemingly sterile settings.

Golimumab-exacerbated subacute cutaneous lupus erythematosus.

BACKGROUND: Subacute cutaneous lupus erythematosus (SCLE) is characterized by annular, nonscarring, photodistributed, or papulosquamous lesions. The disease may be idiopathic, drug induced, or drug exacerbated. OBSERVATIONS: A 66-year-old woman with a history of hypertension, parkinsonism, rheumatoid arthritis, anxiety and depression, and symptoms of Sjögren syndrome was seen with a 1-month history of an eruption on her upper extremities and upper trunk. The eruption had begun 2 to 3 weeks after subcutaneous injection of golimumab for rheumatoid arthritis. She had developed SCLE 2 years previously due to furosemide use and 10 years previously due to hydrochlorothiazide use. Physical examination revealed scaly, annular, erythematous plaques photodistributed on the arms, legs, and upper trunk. A punch biopsy specimen demonstrated vacuolar interface dermatitis and lymphohistiocytic perivascular inflammation. Serological abnormalities included a positive antinuclear antibody, an elevated anti-La/SS-B antibody level, and an elevated anti-Ro/SS-A antibody level. She was diagnosed as having SCLE and was initially treated with desonide lotion, photoprotection, prednisone (40 mg/d) tapered over 6 weeks, and hydroxychloroquine sulfate (200 mg twice daily). Because of persistent disease, methotrexate sodium (12.5 mg/wk) was subsequently added to the regimen, and her eruption cleared completely. CONCLUSIONS: Golimumab should be added to the list of medications capable of inducing or exacerbating SCLE. Our patient demonstrated variable times to the resolution of SCLE, possibly attributable in part to the different half-lives of the agents administered.

Tissue eosinophilia: not an indicator of drug-induced subacute cutaneous lupus erythematosus.

OBJECTIVE: To investigate whether tissue eosinophilia is a differentiating histopathologic feature of drug-induced subacute cutaneous lupus erythematosus (DI-SCLE) compared with non-DI-SCLE. DESIGN: Retrospective medical record review with prospective blinded histopathologic analysis. SETTING: University-affiliated dermatology and dermatopathology practice. PATIENTS: Fifty-nine patients with SCLE were divided into DI (n = 15) and non-DI (n = 44) groups. MAIN OUTCOME MEASURES: A dermatopathologist masked to the etiologic associations reviewed corresponding histopathologic specimens. For each patient, an eosinophil ratio was calculated as the mean eosinophil score (averaging eosinophil counts from 10 high-power histologic fields) divided by the intensity of inflammation. Eosinophil ratios for both groups were compared using the Mann-Whitney test. RESULTS: No significant difference was found in mean eosinophil ratios in the DI vs non-DI groups (0.11 vs 0.004; P = .34). Mucin deposition was present in both populations and was not significantly different (P = .18). The inflammatory infiltrate was superficial and deep in 10 patients (67%) in the DI group vs 24 (55%) in the non-DI group. Periadnexal inflammation was observed in 12 patients (80%) in the DI group vs 37 (84%) in the non-DI group, and basal layer liquefaction with dyskeratosis was seen in 15 patients (100%) in the DI group and in 37 (84%) in the non-DI group. CONCLUSIONS: Tissue eosinophilia is not a differentiating histopathologic feature of DI-SCLE. Careful review of a patient's drug history in correlation with clinical findings remains the standard for identifying a drug as an etiologic or exacerbating factor in patients with SCLE.

Cutaneous protothecosis.

Prototheca species are an achlorophyllic algae that cause infections primarily in immunocompromised individuals. At least one-half of infectious cases are cutaneous. Because protothecosis is seldom suspected clinically, patients may be subjected to various treatment modalities for extended periods without satisfactory results. Cutaneous protothecosis shares similar clinical and pathologic findings with deep tissue fungal mycoses. The typical presentation occurs most commonly on the face and extremities as erythematous plaques, nodules, or superficial ulcers. Prototheca spp are spherical, unicellular, nonbudding organisms that are sometimes noted on routine hematoxylin-eosin staining but are best visualized with periodic acid-Schiff and Gomori methenamine-silver histochemical stains. Although protothecosis can be diagnosed on biopsy, culture of the organism on a medium such as Sabouraud dextrose agar is required for definitive diagnosis. Treatment may require a combination of surgical excision and antifungal agents. Therefore, cutaneous protothecosis should be considered in a lesion that appears suspicious for the more-common fungal infections.

An immunohistochemical comparison between MiTF and MART-1 with Azure blue counterstaining in the setting of solar lentigo and melanoma in situ.

BACKGROUND: Evaluation of cutaneous pigmented lesions can be diagnostically challenging and represents an activity often supplemented by immunohistochemistry. Immunohistochemical studies typically employ 3,3'-diaminobenzidine (DAB) resulting in brown staining of both melanocytes and melanin. Difficulty may thus arise in distinguishing different cell types in heavily melanized lesions. Azure blue counterstaining has been used in conjunction with melanoma antigen recognized by T-cells (MART-1) to differentiate melanocytes from melanin by highlighting the latter blue-green. Microphthalmia transcription factor (MiTF) represents an alternative immunomarker that shows nuclear reactivity, which facilitates ease of interpretation. METHODS: Twenty examples of solar lentigo and melanoma in situ (MIS) were independently evaluated utilizing MiTF and MART-1/Azure blue for melanocyte quantification. Melanocyte counts were averaged over five high-power fields (×400) to obtain a mean melanocytic count. RESULTS: There was no significant difference in the mean melanocytic count between MART-1/Azure blue and MiTF as assessed in the solar lentigo group and as assessed independently in the MIS group. MiTF nuclear staining facilitated interpretation and required less laboratory preparation, as an additional counterstain was not necessary. CONCLUSIONS: MiTF is as effective as MART-1/Azure blue in identifying melanocytes in the context of solar lentigo or MIS. On the basis of our results, we favor expanding the use of MiTF as an immunohistochemical marker, as it provides an efficient alternative to MART-1 with Azure blue counterstaining in the evaluation of cutaneous pigmented lesions.

Cutaneous lymphoproliferative disorder complicating infectious mononucleosis in an immunosuppressed patient.

Infectious mononucleosis is the syndrome produced by primary infection with Epstein-Barr virus during adolescence or early adulthood. In immunosuppressed individuals, depressed T-cell function allows the Epstein-Barr virus-driven B-cell proliferation to continue unabated, potentially leading to a lymphoproliferative disorder. A 15-year-old girl with a history of ulcerative colitis treated with 6-mercaptopurine and mesalamine presented with the acute onset of a rapidly enlarging, ulcerative nodule on her left lower eyelid 4 weeks following recovery from infectious mononucleosis. The biopsy revealed an Epstein-Barr virus-positive lymphoproliferative disorder. Systemic disease was absent. Following discontinuation of 6-mercaptopurine, the patient was treated with two courses of intravenous cyclophosphamide. The lesion resolved completely and she remains disease free at 14 months following diagnosis. We report a solitary cutaneous lesion of an immunosuppression-related lymphoproliferative disorder (IR-LPD) occurring as a complication of infectious mononucleosis, and review the pathogenesis and reported cases of Epstein-Barr virus-related immunosuppression-related lymphoproliferative disorder arising in the setting of inflammatory bowel disease. It is important for dermatologists and dermatopathologists to be aware of the occurrence of IR-LPD in patients being treated for inflammatory conditions, including inflammatory bowel disease. Given the role of primary infection with Epstein-Barr virus in the development of IR-LPD, consideration may be given to assessing Epstein-Barr virus status prior to initiating immunosuppressive therapy in young patients.

Cutaneous sclerosis: a previously undescribed manifestation of sclerosing mesenteritis.

BACKGROUND: Sclerosing mesenteritis is a rare disease of unknown etiology that is characterized by self-limited, nonspecific inflammation and fibrosis of the mesenteric adipose tissue. Histologic classification characterizes 3 main stages in the evolution of the fibroinflammatory process: mesenteric lipodystrophy (ML), mesenteric panniculitis (MP), and sclerosing (retractile) mesenteritis (SM). OBSERVATIONS: A 68-year-old woman with biopsy-proven MP presented with multiple asymptomatic, indurated subcutaneous nodules on both arms, as well as 2 indurated plaques on her abdomen. The cutaneous changes preceded the diagnosis of SM by roughly 3 years. The arm lesions were centrally depressed with a prominent groove and a peau d'orange appearance. Biopsy findings revealed a subcutaneous process with almost total replacement of adipocytes by zones of woody sclerosis and fat necrosis identical to that observed in the mesentery. To our knowledge, this manifestation of sclerosing mesenteritis has not been reported previously. CONCLUSIONS: Sclerosing mesenteritis has rarely been associated with extra-abdominal idiopathic fibrosclerotic disorders, but a cutaneous component of SM has never been characterized. The fact that the cutaneous lesions were histopathologically identical to the mesenteric changes and their presence prior to the recognition of intra-abdominal disease suggests that future patients with such lesions might be evaluated for this disorder leading to earlier recognition.

Atypical fibroxanthoma with regional lymph node metastasis: report of a case and review of the literature.

BACKGROUND: Atypical fibroxanthoma (AFX) is a low-grade sarcoma usually occurring on sun-damaged skin of the head and neck in elderly patients. Metastatic disease has been reported very rarely. The potential aggressiveness of AFX is controversial. OBSERVATIONS: We describe herein a patient who developed metastatic disease in cervical lymph nodes. Our patient was an 87-year-old man with a 7-week history of a rapidly growing AFX presenting as a 1.5-cm sessile nodule on his right mandible. Two months following excision, the patient developed cervical lymphadenopathy. Histopathologic analysis of the cervical lymph nodes revealed spindle-cell tumors with histologic characteristics identical to those of the primary AFX, and the tumors were immunonegative for cytokeratin MNF-116 and S-100. In addition, we review and analyze cases from the literature and articles related to immunohistochemical stains used to diagnose AFX. CONCLUSIONS: Atypical fibroxanthoma is a diagnosis of exclusion, and only a small number of metastatic AFX cases have been reported. A review of the literature pertaining to immunohistochemical stains suggests the potential benefit of use of CD10, procollagen I, CD99, CD117, p63, and LN-2 in differentiating AFX from other spindle-cell tumors. The metastatic potential of AFX may not be fully appreciated, and clinicians should be reminded of its potential aggressive behavior.

Palmoplantar lichen planus: A rare presentation of a common disease.

BACKGROUND: Lichen planus (LP) is a chronic inflammatory skin disease commonly seen by dermatologists. MAIN OBSERVATION: The current case describes palmoplantar lichen planus, a rare variant of this disease that can easily be misdiagnosed. This case describes a patient that presented with multiple papules on his hands and plantar feet that had previously been diagnosed as tinea manum and psoriasis. A biopsy from the patient, however, was diagnostic of lichen planus. The patient was subsequently treated successfully with topical clobetasol propionate 0.05% ointment applied twice daily. CONCLUSIONS: Palmoplantar lichen planus is a rare disease that can be easily misdiagnosed. This case report emphasizes the role of the biopsy when presented with such patients.

Clonal relationships between epidermotropic metastatic melanomas and their primary lesions: a loss of heterozygosity and X-chromosome inactivation-based analysis.

Loss of heterozygosity (LOH) has previously been demonstrated at multiple chromosome microsatellites in primary and metastatic melanomas. Epidermotropic metastases of melanoma are unique in their varied histopathologic appearance, which can mimic a primary lesion. Our objective was to compare LOH profiles in primary and epidermotropic metastatic melanoma to delineate their clonal relationship. We examined the pattern of allelic loss in the primary melanomas of nine patients in addition to the 21 corresponding epidermotropic metastatic melanomas (average 2.3 metastases per patient). DNA samples were prepared from formalin-fixed, paraffin-embedded tissue sections using laser capture microdissection. Eight DNA microsatellite markers on six different chromosomes were analyzed: D1S214 (1p), D6S305 (6q), D9S171 (9p), D9S157 (9p), IFNA (9p), D10S212 (10q), D11S258 (11q), D18S70 (18q). In addition, X-chromosome inactivation analysis was performed in tumors from four women. LOH was seen in 67% (6/9) of primary melanomas and 81% (17/21) of epidermotropic metastatic melanomas. The most frequent allelic losses in informative cases occurred at 10q (33%), 9p (22%), and 11q (22%) in primary melanomas, and at 10q (50%), 1p (44%), and 6q (39%) in epidermotropic metastatic melanomas. Primary lesions demonstrating LOH had concordant allelic loss in at least one locus in a corresponding epidermotropic metastatic melanoma in 83% (5/6) of cases. X-chromosome analysis showed nonrandom inactivation in 75% (3/4) and 71% (5/7) of primary melanoma and epidermotropic metastatic melanoma cases, respectively. Our LOH and X-chromosome inactivation analysis data suggest that epidermotropically metastatic melanomas are clonally related to their primary lesion in many cases. Our data also indicated that some cases diagnosed as epidermotropic metastatic melanoma might be divergent clones or new primaries rather than metastatic disease.

African tick bite fever: a not-so-uncommon illness in international travelers.

BACKGROUND: African tick bite fever is a rickettsial illness that has recently emerged as a significant disease among international travelers. The vector is the Amblyomma tick, which is endemic to sub-Saharan Africa and parts of the eastern Caribbean. OBSERVATIONS: We describe a middle-aged woman who returned from a mission trip to Zimbabwe with an influenzalike illness and inoculation eschar; she also had a history of travel to a game farm. Biopsy revealed a histopathologic pattern consistent with an infectious pathogenesis. Immunohistochemical staining confirmed the presence of rickettsial organisms. In light of the patient's history, the clinical constellation of signs and symptoms, and the results of ancillary laboratory testing, a diagnosis of African tick bite fever was made. The patient was treated with doxycycline hydrochloride and had an uncomplicated course. CONCLUSIONS: This report further highlights the epidemiological and clinical features of African tick bite fever. With the increase in international travel, it is important to recognize the illness in those who have been to endemic countries and to counsel patients regarding preventive measures for planned travel.