Noonan syndrome laboratory findings
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Serge Korjian, Yazan Daaboul
Overview
Overview
Major lab findings in Noonan syndrome are coagulation factor deficiencies, platelet defects, and growth hormone deficiency.
Lab Findings
Lab Findings
Lab findings are usually non-specific in the context of Noonan syndrome. The most common findings are hematological abnormalities especially related to hemostasis. Abnormal bleeding time, prolonged aPTT and PT due to factor deficiencies and platelet defects are not uncommon. In addition, patients can also have several hematological abnormalities, that include monocytosis, thrombocytopenia, and myeloproliferative disorder.[1]
Growth hormone (GH) deficiency and resistance can be seen in Noonan syndrome accounting in part for the associated short stature. Patients with PTPN11 mutations can have increased blood levels of GH in contrast to low concentrations of IGF1.[2]
References
References
- ↑ Roberts AE, Allanson JE, Tartaglia M, Gelb BD (2013). “Noonan syndrome”. Lancet. 381 (9863): 333–42. doi:10.1016/S0140-6736(12)61023-X. PMID 23312968.
- ↑ Binder G, Neuer K, Ranke MB, Wittekindt NE (2005). “PTPN11 mutations are associated with mild growth hormone resistance in individuals with Noonan syndrome”. J Clin Endocrinol Metab. 90 (9): 5377–81. doi:10.1210/jc.2005-0995. PMID 15985475.
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