[Genetic analysis of a patient with dyskeratosis congenita]

Dyskeratosis congenita (DKC) is a rare inherited disease characterized by reticulated pigmentation of the skin, nail dystrophy and oral leukoplakia. More than 90% of DKC cases are inherited as an X-linked recessive trait. Half the patients develop progressive pancytopenia by the age of 11 yr, and this is the leading cause of death. We experienced a 11-year-old boy with the above symptomatic triad of DKC, complicated by progressive pancytopenia as well as cerebellar ataxia. Genetic analysis of mRNA from his cultured peripheral lymphocytes revealed a missense mutation resulting in substitution of 1,150 C with T in the DKC1 gene. This is identical to the mutation reported by Knight et al. to be prevalent in X-linked cases of DKC (11 out of 21 patients). Existence of the identical mutation in Japan suggests that this mutation has been selected on the basis of not only the DNA structural sequence of dyskerin, but also its biological function. We report the detailed clinical course of this Japanese DKC patient with a mutation in the DKC1 gene, and describe the results of genetic analysis.

Oral carcinoma in a young man: a case of dyskeratosis congenita

We report a 28-year-old male with a voluminous growth of the tongue, present for 6 months. The histological examination revealed a squamous cell carcinoma. The patient was also affected by oral leukoplakia, nail dystrophy, reticulated poikiloderma of the neck and hyperkeratosis of palms and soles. On the basis of clinical features and histological findings, as well as findings from the family, the diagnosis of dyskeratosis congenita (DKC) was made.

Overlap of dyskeratosis congenita with the Hoyeraal-Hreidarsson syndrome

X-linked dyskeratosis congenita (DKC) is characterized by mucosal leukoplakia and ulcerations, skin abnormalities, nail dystrophy, and pancytopenia. Hoyeraal-Hreidarsson syndrome (HHS) includes intrauterine growth retardation, microcephaly, mental retardation, cerebellar malformation, and pancytopenia. A patient with striking features of both HHS and DKC has a de novo mutation in the DKC1 gene, known to be responsible for DKC. HHS may be a severe form of DKC, in which affected individuals die before characteristic mucocutaneous features develop.

Correction of bone marrow failure in dyskeratosis congenita by bone marrow transplantation

Dyskeratosis congenita is recognized by its dermal lesions and constitutional aplastic anemia in some cases. We report successful allogeneic bone marrow transplantation in two siblings with this disease from their sister, and their long term follow-up. We used reduced doses of cyclophosphamide and busulfan for conditioning instead of total body irradiation. Also, we report late adverse effects of transplantation which are not distinguishable from the natural course of disease.

Dyskeratosis congenita associated with Hodgkin's disease

Dyskeratosis congenita is a rare, hereditary, multisystem disorder characterized by mucocutaneous changes, pancytopenia and increased incidence of malignancy. Different types of neoplasia have been reported in association with dyskeratosis congenita. We present a second case associated with Hodgkin's disease. Delayed appearance of dermatological signs and association with chronic hepatitis B are other unusual features of this case.

Chronic keratoconjunctivitis associated with congenital dyskeratosis and erythrokeratodermia variablis. Two rare genodermatoses

OBJECTIVE

The purpose of the study was to report the ocular manifestations and immunohistopathologic description of two rare forms of genodermatosis: congenital dyskeratosis (CD) and erythrokeratodermia variabilis (EKV).

DESIGN

Case reports.

PARTICIPANTS

Two patients with CD and EKV presenting with chronic keratoconjunctivitis were studied.

INTERVENTION

Clinical photography to show ocular manifestations and dermatologic findings was performed. Conjunctival biopsy was performed to determine the histopathology and immunohistopathology.

RESULTS

In the patient with EKV, the eyelid skin was dry, erythematous, and thickened. The lid margins showed plugging of some of the Meibomian glands, madarosis, and occasional trichiasis. The epibulbar conjunctiva was injected and had a moderate papillary reaction. Both corneas had pronounced vascularization and stromal scarring. Conjunctival biopsy results disclosed a striking number of degranulating mast cells and moderate numbers of plasma cells. Immunohistopathology showed pronounced immunoglobulin G (IgG)-positive cells in the stroma and immunoglobulin A (IgA) positivity in the epithelium. There was scattered immunoglobulin M (IgM) and moderate C3 and C4 positivity in the stroma. In CD, the patient had keratinized lid margins, entropion formation, trichiasis, cicatrizing conjunctivitis, and symblephra formation. The corneal surface was keratinized, with deep and superficial vascularization. Conjunctival biopsy specimens showed pronounced epithelial keratinization and squamous metaplasia. Degranulating mast cells and eosinophils were prominent in the stroma. Immunohistopathology showed C4 and immunoglobulin D positivity on the keratinized epithelial surface with rare foci of immunoglobulin E-positive cells. Basal epithelial cells were positive for IgA and IgG, and a large number of IgA and IgG plasma cells were present in the substantia propria.

CONCLUSION

To the authors' knowledge, these case reports represent the first clinical description of the ocular manifestation of EKV and the first immunohistopathologic description of the affected conjunctiva in EKV and CD, both of which should be considered in the differential diagnosis of genodermatosis associated with chronic keratoconjunctivitis.

Dyskeratosis congenita and associated interstitial lung disease: a case report

We describe a male patient with dyskeratosis congenita who, in addition to the classic triad, also suffers from usual interstitial pneumonia. He was treated with methyl-prednisolone but it is not clear whether this had an influence on the course of the disease.

Aplastic anaemia and reticulated skin hyperpigmentation

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[A case of dyskeratosis congenita with acute interstitial pneumonia]

This is a rare case of Dyskeratosis Congenita (DC) with acute interstitial pneumonia. A 51-year-old man with DC was admitted to our hospital because of cough, sputum and fever. Chest X-ray film showed ground glass opacities in all lung fields for a while steroid's therapy proved effective, but about seven months later the patient's condition became serious. Methylprednisolone, cyclophosphamide and mechanical ventilation therapy were not effective. He died and an autopsy was performed. The lung specimen showed Organizing Diffuse Alveolar Damage, and some parts pointed to bacterial infection. But Pneumocystic carinii pneumonia and Fungal infections were not found. It is therefore necessary to conduct intensive examinations of lung involvement of patients with Dyskeratosis Congenita.