Crowe sign

The Crowe sign or Crowe's sign is the presence of axillary (armpit) freckling in people with neurofibromatosis type I (von Recklinghausen's disease). These freckles occur in up to 30% of people with the disease and their presence is one of seven diagnostic criteria for neurofibromatosis. Freckles can also be present in the intertriginous area in neurofibromatosis, such as the inguinal fold, submamillary areas and nape of the neck.

This medical sign is named after Frank W. Crowe, an American physician.[1] He noticed that axillary freckles are present in about 20-30% of patients with neurofibromatosis, but he did not see any in patients who did not have neurofibromatosis.

Axillary freckling also occurs in other disease processes that closely resemble NF1, such as Legius syndrome (cafe-au-lait spots, axillary freckling, and macrocephaly without Lisch nodules, neurofibromas or CNS tumors), and, homozygous HNPCC mutations (cafe-au-lait spots, axillary freckling, and cutaneous neurofibromas in the setting of Hereditary Non-Polyposis Colon Cancer, also known as Lynch syndrome; seen with family history of HNPCC and consanguinity)[2]

References

  1. Crowe, Frank (1956). A clinical, pathological and genetic study of multiple neurofibromatosis. Thomas, Charles C. Publisher, Ltd. ISBN 9780398003708.
  2. K Jett, JM Friedman. Clinical and Genetic Aspects of Neurofibromatosis 1. Genetics in Medicine 12(1):1-11. January 2010.