2024 Volume 40 Issue 2 Pages 111-115
Kallmann syndrome is a genetic disease that combines hypogonadotropic hypogonadism and olfactory abnormality, with various accompanying symptoms depending on the genetic type. The patient in this case was a 3-year-old boy. At a health checkup at 1.5 years old, poor eye contact was noted, which led to strabismus, left eyelid ptosis, and left amblyopia. A head MRI scan incidentally revealed the absence of the olfactory bulb, olfactory sulcus, and olfactory tract. Kallmann syndrome was suspected. Subsequent examination revealed low gonadotropin levels and a pathogenic variant of the ANOS1 (KAL1) gene, leading to a definitive diagnosis of Kallmann syndrome. Abdominal MRI and renal scintigraphy revealed that the patient had a single right kidney. Kallmann syndrome is often diagnosed with delayed onset of puberty, but due to the various accompanying symptoms, it may be possible to make an early diagnosis based on symptoms such as ptosis, amblyopia, and renal hypoplasia. In addition, the absence of the olfactory bulb, olfactory groove, and olfactory tract on head MRI is a characteristic finding of Kallmann syndrome and is useful for diagnosis.
