Autosomal dominant familial acanthosis nigricans caused by a C-terminal nonsense mutation of FGFR3.

FGFR3 encodes a transmembrane receptor tyrosine kinase that has six autophosphorylation sites of tyrosine. Among them, Y770 is a negative regulatory site for the downstream signaling of FGFR3. Constitutive active mutations in FGFR3 are involved in human developmental disorders including familial acanthosis nigricans, an autosomal dominant disorder characterized by general hyperpigmentation with mild acanthosis of the epidermis. Here, we report two unrelated cases of familial acanthosis nigricans with a heterozygous c.2302G>T (p.E768*) mutation in FGFR3 (NM_000142.5). FGFR3 mRNA purified from the skin lesion neither showed aberrant splicing nor nonsense-mediated mRNA decay, indicating that the FGFR3 mutant simply lacked the C-terminal 768-806 amino acids including Y770. While all of the known pathogenic mutations were missense mutations in FGFR3 showing autosomal dominant trait, the c.2302G>T mutation of FGFR3 is a unique autosomal dominant nonsense mutation that causes familial acanthosis nigricans probably via loss of negative regulatory autophosphorylation site of FGFR3.

Case of Mycobacterium haemophilum misdiagnosed as Mycobacterium intracellulare due to one base insertion in the bacterial genome.

Mycobacterium haemophilum is a slow-growing, non-tuberculous mycobacteria that causes cutaneous infection. We describe a case of cutaneous infection in a 68-year-old Japanese man with polymyositis. This was caused by M. haemophilum harboring one base insertion in gene sequence. At first, the causal microorganism was misidentified as M. intracellulare by COBAS® TaqMan® MAI test. However, poor growth on Ogawa media and growth enhancement on 7H11C agar around a hemin-containing disk prompted us to reinvestigate the causal microorganisms, which were revealed to be M. haemophilum. Amplified polymerase chain reaction products were sequenced, and the 16S rRNA gene, rpoB, hsp65 and internal transcribed spacer region sequences showed a 100%, 100%, 99.66% and 99.7% match, respectively, with the corresponding regions of M. haemophilum, but it harbored a novel gene sequence in hsp65. The sequences determined by gene analysis of the M. haemophilum strain were deposited into the International Nucleotide Sequence Database. Although numerous cases of M. haemophilum infection have been reported in other countries, only six cases have been reported in Japan to date. It could be possible that this novel mutation lead to misdiagnosis. As M. haemophilum prefers a lower growth temperature (30-32°C) and it requires iron in the culture medium, M. haemophilum could be misidentified or overlooked. Accordingly, a M. haemophilum infection should be considered in cases of cutaneous infection of the body sites, of which surface temperature is low.

A case of microscopic polyangiitis with skin manifestations in a seven-year-old girl.

A case of a 7-year-old girl with microscopic polyangiitis (MPA) with a skin eruption characterized by maculopapular, erythematous and purpuric lesions on the face, elbows, and knees is presented. Anti-neutrophil cytoplasmic autoantibodies (ANCA) with myeloperoxidase specificity (MPO-ANCA) were identified. Chest X-ray and computed tomography scan revealed diffuse infiltrates in both lung fields, suggesting alveolar hemorrhage. Microscopic hematuria was detected but a renal biopsy showed no abnormalities. Histological examination of a skin biopsy from a purpuric papule showed leukocytoclastic vasculitis of the small vessels in the entire dermis. The patient was treated with prednisolone and mizoribine, resulting in an improvement in the skin lesions except for those on the knee.

Sweet's syndrome with panuveitis resembling Behçet's disease.

PURPOSE: Sweet's syndrome (SS) is a skin disorder clinically characterized by fever, neutrophilia, and painful edematous plaques that occasionally causes posterior uveitis. We present two cases of SS with panuveitis resembling Behçet's disease (BD). SUBJECTS: Two patients with panuveitis associated with SS. OBSERVATIONS: The patient in case 1 was a 57-year-old Japanese man who developed acute severe iritis with hypopyon in the left eye. Fluorescein angiography (FA) performed 1 month after treatment showed findings observed in posterior uveitis: dye leakage from the optic disc and a petaloid pattern of hyperfluorescence in the macular region. The patient in case 2 was a 64-year-old Japanese man who complained of blurred vision in his left eye. Faint flare and occasional cells were present in the left anterior chamber, 2+ cells in the anterior vitreous, and 2+ vitreous opacification in the left eye. FA demonstrated dye leakage from the optic disc and peripheral capillary vessels in both eyes. Both patients were diagnosed as having SS on the basis of fever, neutrophilia, elevated C-reactive protein, and skin biopsy results of neutrophilic infiltration without vasculitis. CONCLUSIONS: Differentiation of SS from BD based on the ocular manifestations is difficult. Ophthalmologists should bear in mind that SS can exhibit panuveitis resembling BD.

Docetaxel: a therapeutic option in the treatment of cutaneous angiosarcoma: report of 9 patients.

BACKGROUND: Effective treatment options are limited for patients with cutaneous angiosarcoma (AS). Docetaxel, a member of the taxane family of drugs, reportedly has been effective in the treatment of lung, head and neck, and breast cancers. Another taxane drug, paclitaxel, reportedly had unique activity in the treatment of AS of the scalp and neck and acquired immunodeficiency syndrome-related Kaposi sarcoma. Therefore, the authors hypothesized that docetaxel may be of value in the treatment of cutaneous AS that is resistant to conventional therapy. However, there were only 3 case reports of the successful treatment of AS in elderly patients using docetaxel in combination with surgery and radiotherapy. METHODS: This was a retrospective trial. After written informed consent was obtained, docetaxel was administered intravenously at a dose of 25 mg/m(2) for 1 hour weekly over a period of 8 weeks on the basis of previous reports. This treatment regimen was received by 9 patients with cutaneous AS who were treated at Kobe University Hospital between January 2003 and October 2006. RESULTS: Six of the 9 patients who received treatment achieved major responses, including 2 complete responses and 4 partial responses. Neutropenia and peripheral neuropathy were not prominent, although severe radiation dermatitis enhanced by the docetaxel was observed in 3 patients. There were no deaths attributable to this therapy. CONCLUSIONS: The current study demonstrated that docetaxel was effective in patients with cutaneous AS.