Long-Lasting Catch-up Growth under Bio-Methionyl Growth Hormone Treatment in an Infant with Isolated Growth Hormone Deficiency Type 1A1

ABSTRACT. This case report concerns a 7-month-old infant with severe height retardation (–5.0 SD), typical growth hormone (GH)-deficient phenotype, and undetectable GH serum levels in response to three pharmacological stimuli. Diagnosis of isolated GH deficiency type 1A was confirmed by restriction endonuclease analysis of genomic DNA which pointed out GH-N gene deletion. The introduction of bio-methionyl-GH therapy in this patient was followed by a transient and clinically irrelevant appearance of low binding capacity GH antibodies as well as by a long-lasting catch-up growth (42.2 cm) which is continuing 44 months after beginning of treatment. This atypical pattern confirms that immune and growth response to exogenous GH in isolated GH deficiency 1A may be very heterogeneous.     

A new c-kit mutation in a case of aggressive mast cell disease

Systemic mast cell disease (SMCD) is a disorder characterized by a mast cell proliferation in various tissues. Mast cells express the c -kit proto-oncogene. A few cases of c -kit mutations have been described in SMCD. We report an aggressive SMCD in a patient who presented with a bone marrow infiltration by abnormal mast cells. Molecular studies of mast cell DNA and RNA revealed a new c- kit heterozygous mutation (Asp820Gly). This mutation leads to a drastic amino-acid change and is located close to the highly oncogenic Asp816Val. These findings suggest that the Asp820Gly has a potential role in c- kit activation.