[Show abstract][Hide abstract] ABSTRACT: Dowling-Degos disease (DDD) is an autosomal-dominant genodermatosis characterized by progressive and disfiguring reticulate hyperpigmentation. We previously identified loss-of-function mutations in KRT5 but were only able to detect pathogenic mutations in fewer than half of our subjects. To identify additional causes of DDD, we performed exome sequencing in five unrelated affected individuals without mutations in KRT5. Data analysis identified three heterozygous mutations from these individuals, all within the same gene. These mutations, namely c.11G>A (p.Trp4(∗)), c.652C>T (p.Arg218(∗)), and c.798-2A>C, are within POGLUT1, which encodes protein O-glucosyltransferase 1. Further screening of unexplained cases for POGLUT1 identified six additional mutations, as well as two of the above described mutations. Immunohistochemistry of skin biopsies of affected individuals with POGLUT1 mutations showed significantly weaker POGLUT1 staining in comparison to healthy controls with strong localization of POGLUT1 in the upper parts of the epidermis. Immunoblot analysis revealed that translation of either wild-type (WT) POGLUT1 or of the protein carrying the p.Arg279Trp substitution led to the expected size of about 50 kDa, whereas the c.652C>T (p.Arg218(∗)) mutation led to translation of a truncated protein of about 30 kDa. Immunofluorescence analysis identified a colocalization of the WT protein with the endoplasmic reticulum and a notable aggregating pattern for the truncated protein. Recently, mutations in POFUT1, which encodes protein O-fucosyltransferase 1, were also reported to be responsible for DDD. Interestingly, both POGLUT1 and POFUT1 are essential regulators of Notch activity. Our results furthermore emphasize the important role of the Notch pathway in pigmentation and keratinocyte morphology.
Full-text · Article · Jan 2014 · The American Journal of Human Genetics
[Show abstract][Hide abstract] ABSTRACT: Mycosis fungoides (MF) is the most common type of cutaneous lymphoma and has protean clinicopathological manifestations. Follicular or folliculotropic MF (FMF) is a rare variant, which histopathologically is characterized by pronounced folliculotropism of neoplastic T cells, with or without follicular mucinosis, and clinically by an impaired prognosis compared to classic MF. In contrast, unilesional MF is a very rare variant with an excellent prognosis, with a single case of large-cell transformation reported to date. The combination of folliculotropic and unilesional MF is very unusual, with only two cases reported to date. Here we report two patients with unilesional folliculotropic MF with progression to tumor stage in both patients. To the best of our knowledge, this is the first report on the disease evolution with large-cell transformation and progression of unilesional FMF. Complete remission was achieved by local radiation therapy in both patients. The differential diagnoses, classification and implications for the treatment of unilesional FMF as well as the pertinent literature are discussed.
No preview · Article · Aug 2012 · Journal of Cutaneous Pathology
[Show abstract][Hide abstract] ABSTRACT: Photodynamic therapy (PDT) is an established treatment for basal cell carcinomas (BCCs). Although recurrences are sometime observed, their histological patterns have never been specifically studied or compared with the one of the initial tumor.
To compare the histopathological aggressiveness of BCCs recurring after PDT with that of the primary tumors.
The study population included 12 patients with 16 post PDT recurrent BCCs. Outcome measures were proportion of histologically aggressive subtypes in BCC recurrences vs. primary tumor.
62.5% of recurrent BCCs displayed a transition from a non-aggressive to an aggressive subtype.
Post PDT recurrences appear to display an increased histological aggressiveness, although the latter may reflect the natural course of tumor progression. Despite the presence of potential biases, our study raises the possibility that PDT favors the selection of more aggressive tumor cells. Better systematic large-scale follow-up studies are required to assess the exact frequency and histological types of BCC recurrences after PDT.
[Show abstract][Hide abstract] ABSTRACT: Merkel cell carcinoma (MCC) is an aggressive cutaneous tumor whose clinical presentation, usually a pink nodule, is not specific. We aimed in this study to determine the dermoscopic criteria encountered in MCC.
From our image database we selected the patients diagnosed with MCC and scored the dermoscopic criteria shown by these tumors.
Ten patients coming from three different academic hospitals were studied. Vascular structures were the more relevant dermoscopic features. In 8 out of 10 (80%) patients a polymorphic vascular pattern was seen, composed of milky-red clods/areas in association with one or more additional vascular structures.
Although an overlap existed between the dermoscopic features observed in MCC and amelanotic melanoma, the presence of a polymorphous vascular pattern may constitute an additional clinical clue to accurately diagnose this rare tumor.
[Show abstract][Hide abstract] ABSTRACT: Overlap syndromes represent disorders that combine diagnostic criteria of two or more different connective tissue diseases.
We herein describe the case of a 34-year-old patient.
Our patient developed a lesion on the scalp and forehead following Blaschko's line typical for linear morphea "en coup de sabre", while histopathological features were consistent with both chronic cutaneous lupus erythematosus and linear morphea, a cutaneous overlap syndrome previously described as linear sclerodermiform lupus erythematosus. The patient was given oral antimalarials in association with topical steroids and calcineurin inhibitors with good response.
Knowledge of this peculiar cutaneous overlap syndrome is warranted, since its management and prognosis is probably different from classical linear morphea.
No preview · Article · Dec 2011 · International journal of dermatology
[Show abstract][Hide abstract] ABSTRACT: Cutaneous T-cell lymphoma can be associated with clinically significant nail alterations, the presentation of which can be protean and misleading. To date, only a few reports have demonstrated direct specific tumor infiltration of the nail bed, while little is known about the efficacy of topical treatments.
We describe the case of a 93-year-old man presenting with Sézary syndrome who developed clinically significant nail alterations. Light microscopy studies and T-cell receptor rearrangement analysis demonstrated the presence of a specific lymphocytic infiltrate within the nail bed. The patient was given repeated courses of topical mechlorethamine, leading to a sustained complete remission of both skin and nail alterations.
Specific nail involvement should be recognized and considered in all patients with cutaneous T-cell lymphomas. Topical mechlorethamine remains an attractive therapeutic option in cases of specific nail alterations, especially for situations in which systemic therapies are either not indicated or unlikely to be well tolerated.
No preview · Article · Nov 2010 · Archives of dermatology
[Show abstract][Hide abstract] ABSTRACT: Multiple cutaneous and uterine leiomyomata syndrome (MCUL; MIM 150800) is a rare condition that sometimes predisposes to renal cancer. It is caused by deleterious mutations in the fumarate hydratase (FH) gene. In many patients, skin leiomyomas have been reported to develop according to a segmental type 1 or type 2 distribution. We report a patient showing multiple leiomyomas distributed according to a segmental type 2 distribution and covering several areas exclusively on the left side of his body.
To search for a specific mutation in the FH gene associated with this phenotype.
Genomic DNA from peripheral blood leucocytes of the proband was sequenced and screened for mutation of the FH gene.
Heterozygosity for an as yet undescribed mutation c.695delG, leading to a truncated protein p.Gly232AspfsX24, was found.
We report a new mutation in the FH gene and discuss the unusual pattern of purely unilateral distribution in the present case.
[Show abstract][Hide abstract] ABSTRACT: Chronic meningococcemia (CM) is a diagnostic challenge. Skin lesions are frequent but in most cases nonspecific. Polymerase chain reaction (PCR)-based diagnosis has been validated in blood and cerebrospinal fluid for acute Neisseria meningitidis infection, in patients in whom routine microbiologic tests have failed to isolate the bacteria. In 2 patients with CM, we established the diagnosis by a newly developed PCR-based approach performed on skin biopsy specimens.
Two patients presented with fever together with systemic and cutaneous manifestations suggestive of CM. Although findings from blood cultures remained negative, we were able to identify N meningitidis in the skin lesions by a newly developed PCR assay. In 1 patient, an N meningitidis strain of the same serogroup was also isolated from a throat swab specimen. Both patients rapidly improved after appropriate antibiotherapy.
To our knowledge, we report the first cases of CM diagnosed by PCR testing on skin biopsy specimens. It is noteworthy that, although N meningitidis-specific PCR is highly sensitive in blood and cerebrospinal fluid in acute infections, our observations underscore the usefulness of PCR performed on skin lesions for the diagnosis of chronic N meningitidis infections. Whenever possible, this approach should be systematically employed in patients for whom N meningitidis infection cannot be confirmed by routine microbiologic investigations.
Full-text · Article · Jul 2008 · Archives of dermatology