Review Question - QID 104621

This female patient presenting with amenorrhea and short stature likely has Turner Syndrome. A karyotype analysis is used to confirm this diagnosis.

Turner syndrome (TS) is caused by the partial or complete absence of the second X chromosome in females. TS has several characteristic features including short stature, webbed neck, low posterior hairline, broad chest with widely spaced nipples, cardiac abnormalities, gonadal failure and amenorrhea. Diagnosis is often suspected based on characteristic physical features and is confirmed through karyotype analysis.

Morgan reviews the diagnosis of Turner syndrome. TS can be confirmed with a standard karyotype and will often reveal that the patient is missing an X chromosome (with a karyotype of 45,X) or has both cells missing an X chromosome and normal cells resulting in mosaicism (with a karyotype of 45,X/46,XX). Delayed diagnosis is common in females with short stature.

Sybert and McCauley review TS and the timing of its diagnosis. Prenatal diagnosis of TS can be made based on the ultrasound finding of fetal edema and/or an abnormal triple screen (human chorionic gonadotropin, estriol and alpha-fetoprotein) while newborns can be diagnosed with TS based on hand and foot swelling and redundant nuchal skin. In addition to other phenotypic findings, children may be diagnosed based on short stature and adolescents based on stature and a lack of pubertal development.

Figure A illustrates a female patient with the typical physical features of Turner syndrome.
Illustration A depicts some of the common findings in patients with TS.

Incorrect answers:
Answer 1: Patients with TS may have hypothyroidism, but a TSH test would not be helpful in confirming diagnosis of the overall syndrome.
Answers 2 and 4: An echocardiogram or cardiac MRI might uncover the presence of cardiovascular anomalies often present in patients with TS, but these tests are not used to diagnose the syndrome.
Answer 5: Although it could explain the amenorrhea, pregnancy would not explain the short stature and other physical characteristics in this patient and would not be useful in diagnosing TS.