In what other clinical settings can a telogen effluvium occur?

Normally, about 10% of scalp hairs are in the telogen (preshedding) phase at any given time. Whenever an abnormally large number of otherwise normal telogen hairs are present, a telogen effluvium occurs. There are several clinical situations in which a telogen effluvium is found, including severe illness such as metastatic cancer, but any serious illness or major surgical procedure can also result in a telogen effluvium. The most common form of telogen effluvium occurs in women about 3 months after giving birth. In addition, virtually all newborn infants develop a telogen effluvium during the first 6 months of life, which is why many babies have more hair at birth than at 3 to 4 months after birth.

Causes of telogen effluvium can be summarized as follows:
• Physiologic effluvium of the newborn
• Postpartum
• Postfebrile (e.g., malaria)
• Severe infection
• Debilitating chronic illness
• Postsurgical (major procedure or major trauma)
• Hypothyroidism and other endocrinopathies
• Crash or liquid protein diets; starvation
• Drugs: Retinoids, anticoagulants, anticonvulsives, antithyroid, heavy metals.

Sperling LC: Hair and systemic disease, Dermatol Clin 711–726, 2001.