The diagnosis of tuberous sclerosis complex (TSC) was unknown to Steve's family until his sister Amy was diagnosed in 1984. Incredibly, the confirmation that Amy has TSC eventually led to the diagnosis of many other family members, spanning three and possibly four generations. Steve now has two young sons, both of whom have inherited the disorder. Although within the family, the symptoms of TSC vary from individual to individual, all family members with TSC are mildly affected. Watch Steve's video [duration 6:15] or read the transcript.
When Steve's sister Amy was a freshman in college, she began having headaches and vomiting, symptoms she attributed at first to the flu. The headaches continued intermittently over the next three months and eventually became serious enough for Amy to make an appointment at the student health center. At that time she developed double vision and saw an ophthalmologist as well. The eye exam revealed swelling of the optic nerve, a strong indication of the presence of a brain tumor. The following day Amy had a CT scan, which showed the cause of her symptoms: a subependymal giant cell astrocytoma (SEGA) that was blocking the flow of spinal fluid and causing significant intracranial pressure. The following Friday, a week after she had initially gone to the student health center, Amy had surgery.
The neurosurgeon opted to remove only part of the tumor, fearing that removal of the entire tumor might cause Amy other neurological problems. Because the remaining part of the tumor was still blocking spinal fluid, Amy had a second surgery a month and a half later to place a shunt in her brain. This section of plastic tubing allows excess cerebrospinal fluid to pass from the cranium to the abdomen, where it is safely absorbed into the blood stream. The shunt surgeons placed in Amy's cranium effectively relieved both the intracranial pressure and the neurological symptoms that led to her TSC diagnosis.
Amy's neurosurgeon was familiar with the symptoms of TSC and recommended that Amy be evaluated for the disorder. Amy's doctors also knew that TSC can be inherited. Following her diagnosis, all of Amy's immediate family members were evaluated as well. Amy's siblings, Steve and Ann, as well as their father, Bruce, were all diagnosed with TSC based on the presence of two major diagnostic features: tubers in the brain and more than three hypomelanotic macules.
Amy's diagnosis also led to the diagnosis of an uncle and two cousins. The family now suspects that the disorder was passed down from Steve, Amy, and Ann's paternal grandmother. The grandmother was never officially diagnosed, although a brain scan for other reasons late in her life revealed findings consistent with TSC.
All members of this family who have TSC are mildly affected, which is highly unusual. Typically there is more variability from one generation to the next, particularly with neurological complications such as seizures, cognitive impairment, and behavioral issues. Aside from the complications caused by Amy's SEGA, and seizures experienced by one of Amy and Steve's cousins, TSC has had very little impact on this family. Despite this fortunate family history, doctors are unable to predict how TSC might affect future generations.
The Next Generation
Steve and his wife, Nancy, now have children of their own: two young boys, Anders and Jonas. Both boys have been diagnosed with TSC and both are mildly affected, although Anders did have seizures and was on an antiepileptic drug for about a year and a half when he was a toddler.
Because TSC's effects can change over time, Steve and Nancy know that Anders and Jonas will continue to require periodic monitoring for signs of the disorder. Specialists contend that early intervention is the most reliable means of preventing significant problems caused by TSC. To identify potential problems early, Anders and Jonas undergo regular TSC screenings, including tests for possible brain and kidney involvement and learning problems. And when they are old enough they will receive genetic counseling to understand the risks of passing on TSC to their own children.