Metronidazole (also known as Flagyl® or Metrolyl®) may cause acute liver failure in children with Cockayne syndrome and should be avoided. Please alert your doctors to this.

Health professionals can obtain further information from Dr. Brian Wilson

Any further drug reactions in this patient group should be reported to the regulatory authorities in your own country.
Cockayne syndrome (CS) is a rare disorder, characterised by small stature, microcephaly (having a small head) , developmental delay and premature pathological ageing. It is caused by mistakes in one of two genes: CSA (also called ERCC8) or CSB (also called ERCC6). In order to develop CS, an affected individual must have mistakes in both copies of one of these genes. In most cases, each parent will be a carrier for the condition (i.e. they have a mistake in one of their copies of the gene). This is described as recessive inheritance and means that there is a 25% chance that any children the couple have will be affected by CS. 
Cockayne syndrome is a variable condition, making early diagnosis difficult. Birth weight and head circumference are often normal, as is early development. Reduction in how fast an affected child grows, leading to small stature with a disproportionately small head (microcephaly), may be the first clue to the diagnosis. After the age of 12 months, development is often delayed. Other clinical problems in CS include hearing loss (of any type, but affecting both ears), cataracts, visual impairment due to retinal degeneration, tremor, walking and balance problems (ataxia), joint contractures, progressive loss of body fat and abnormal sensitivity of skin to sunlight. Affected individuals may not experience all of these features. Children with CS can look completely normal early in life, but many develop a sunken appearance to their eyes, and some have facial features (eyes and nose) that appear a little closer together than expected (described as crowded facial features).

If your child has CS, it is important to be aware that they should not be given metronidazole (a type of antibiotic), as this causes liver failure in affected individuals and can be fatal.

Cockayne syndrome is a progressive and incurable condition, with a mean age at death of 8.4 years. The development of early cataracts (under 3 years) is the most significant indicator of how a patient is likely to progress. Approximately 60% of patients with early cataracts survive to 5 years; for those who have no cataracts or develop them after 3 years of age, survival at 5 years is approximately 95%. However, there can be considerable differences between affected members of the same family, making it difficult to predict long term outcomes in CS.

For more detailed information on Cockayne syndrome, including guidelines for care, please see this publication which is available open access through the generosity of the Amy and Friends Cockayne syndrome support group.