Kowarski syndrome

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at August 17, 2016
StartDiseasesKowarski syndrome

Kowarski syndrome is considered to be a rare disease by the National Institutes of Health (NIH). At its core, Kowarski syndrome is a disease characterized by growth problems. Kowarski syndrome is sometimes called pituitary dwarfism. To date, only a handful of cases have been presented for medical study, and therefore there is much left to be discovered about Kowarski syndrome.

Contents

Definition & Facts

Kowarski syndrome is so rare that it is called an orphan disease which is a rare disease that affects less than 200,000 people. The syndrome was first detected in the late 1970's by a pediatrician and researcher named Allen Kowarski along with four additional researchers. The disease is now named after Dr. Kowarski.

Symptoms & Complaints

The chief symptom of Kowarski syndrome is short stature. However, the short stature also produces a number of physical characteristics that can be helpful in identifying Kowarski syndrome. The chief symptoms reported to date by individuals include the following:

Causes

Because so few cases have been reported, the current data on Kowarski syndrome is incomplete. However, various theories have been put forward and there is a known genetic trigger in a gene called GH1 (growth hormone 1). This gene is responsible for controlling production of a protein called somatotropin. Somatotropin is part of a family of proteins that control for growth.

When functioning as it should, the GH1 gene stimulates the body to secrete appropriate amounts of somatotropin to regulate growth. GH1 also supports the body in absorbing sufficient quantities of appropriate amino acids to make protein to aid in physical growth.

In Kowarski syndrome, it is thought that low activity of the GH1 gene combined with low output of somatotropin is responsible for the onset of the syndrome and the symptoms associated with the disease.

Unfortunately, the few patients that have been studied have not shed sufficient light on whether Kowarski syndrome is spontaneous or heritable, a combination of each or neither. It is thought that a heritable aspect may be present as an autosomal recessive gene, which means that an individual would have to receive the genetic mutation from both parents in order to be at risk of developing the syndrome.

Diagnosis & Tests

Diagnosing Kowarski syndrome involves two aspects: cataloguing symptoms and looking for possible mutations associated with the GH1 gene or ineffective GH1 activity. Kowarski syndrome presents before birth (neonatal) or at birth, and it is rarely possible to detect the syndrome at such an early age unless there is another reason to test for activity in the GH1 gene.

Typically, it takes at least two to three years before the individual's growth can be seen to be delayed to a significant level in which primary symptoms - short stature and delayed bone and developmental growth - are detectable and would prompt a genetic test. The genetic test for Kowarski syndrome involves sequencing the GH1 gene to look for low somatotropin production.

Because Kowarski syndrome has not been studied thoroughly, one of the possible diagnostic tests is also one of the possible treatment options. This test is to administer a short course of growth hormone (6 months or less). However, most treating physicians are very reluctant to order administration of growth hormone, either as a test or as a potential form of treatment. Certain endocrine tests and other related tests may also be done to narrow down the diagnosis as follows:

  • Serum growth hormone level test. This test should be done before and after a period of physical activity.
  • Resting somatomedin-C level. This test looks for average levels of somatomedin across time.
  • Dexamethasone suppression test. This test looks for abnormal adrenal gland functioning as related to growth.
  • CT (computerized tomography) scan of the skull. This test examines the skull for abnormal delays in growth patterns.
  • Growth measurement test comparison. This test compares the individual's growth to date with the average growth rate for age, gender and ethnicity.

Additional tests, such as calcium levels in the urine and blood, a CBC blood test, a thyroid function testing and X-ray tests of the bones and skull may be ordered as a way to rule out other diseases with similar symptoms and narrow down the diagnosis.

Treatment & Therapy

Currently, treatment options all focus on management of symptoms. What little is known about successful treatment to date highlights supplementation of the body's natural production of growth hormone, specifically somatomedin.

For the very few number of cases in which treatments have been administered thus far, this treatment has been shown to produce positive results. Results showed increased metabolic activity when growth hormones were artificially administered. This in turn triggered accelerated growth where before growth had been delayed.

Prevention & Prophylaxis

At the moment, there is so little information known about Kowarski syndrome itself that no trustworthy route towards prevention has been identified. It may be possible for prospective or expectant parents to use gene testing to identify mutations in the GH1 gene, but even if both parents show the same mutation, it is not yet possible to know how great the risk is to the unborn baby for developing Kowarski syndrome.

For now, the best course of action remains to closely monitor early growth and development and use gene testing and growth hormone therapy to remedy growth delays.