The inaugural Homocystinuria Network America Conference was held April 21st-22nd in Westford, MA.
The families in attendance traveled from all across the US for the event. They all have different stories, varying symptoms, lengths of time they have been diagnosed, and ages (the youngest patient was only five months old!) but all were quickly made to feel at home. Despite the variation in individual stories, every family shared relatable experiences with one another.
The event featured wonderful speakers, including Dr. Harvey Levy himself and Dr. Kim Chapman, who detailed the ins and outs of HCU.
Homocystinuria is a metabolic condition in which, in the classical form, is caused by a missing or defective liver enzyme that prevents homocysteine from being metabolized into cystathionine. For some people, B6 supplements can help the enzyme to function correctly.
A methionine-restricted diet keeps levels of homocysteine from getting too high because the body does not produce methionine, it is something that we can only obtain through our diets.
Homocysteine needs to be metabolized into cystathionine but without the necessary enzyme (CBS) it cycles back into methionine. Therefore, an increase of methionine in the diet increases the amount of homocysteine in the body. In other words, the pathway that would reduce the amount of homocysteine is “blocked” so it “recycles” back into what it started as, methionine.
Methionine isn’t measured in a lot of foods, so it can be difficult to figure out the levels of methionine in grocery store purchases. For this reason, many people living with HCU navigate food shopping via the amount of protein per serving.
In order to still obtain the protein their body, like all of ours, needs to function, people with HCU also drink a medical formula several times a day as a supplement.
If a patient is properly treated, they should be drinking enough of the formula to prevent their bodies from going into a catabolic state, in which their bodies would begin to breakdown their own muscles for energy. For this reason also, they need to ensure that they are getting enough calories every day, despite their dietary restrictions, to sustain themselves.
The medical formulas haven’t been known to taste the best, and the strict diet can be difficult to adhere to when so many social things tend to involve food.
Some tips and tricks shared at the conference to make adherence a little easier were presented by dietitian, Krista Viau, PhD, RDN, CSP:
- Involve the whole family in food prep
- Replace serving utensils with measuring cups
- Consider pre-measured foods
- Use pre-portioned Tupperware
- Keep some go-to lo-pro snacks on hand
- Have some pantry essentials that you can get from a grocery store in case there’s ever an issue with your shipments of medical food
- Try to serve one dish at meal times that is shared and everyone eats
- Experiment with different spices so that go-to meals feel less repetitive
- Use an app or website to help track your protein intake and distribution (see list of resources at the bottom of the article)
Dr. Chapman explained that HCU, while quite prevalent in other parts of the world, such as Qatar, is a rare condition within the US. Some people with HCU have been misdiagnosed with Marfan’s syndrome. The two disorders can present similarly; people with either disorder may be tall and thin, with long arms and legs, and the lenses of their eyes may detach(ectopia lentis). However, other parts of the body may be impacted by high levels of homocysteine.
Besides ectopia lentis, people with HCU may also be nearsighted. In addition to excessive height and long limbs, their skeletal system may be impacted with bone deformities and osteoporosis (even in children).
The vascular system can also be effected. People with HCU are at a higher risk of thromboembolism, blood clots in their legs and lungs and stroke. These risks increase with dehydration, poorly controlled homocysteine levels, inactivity, pregnancy and estrogen-based medications.
HCU can also impact the central nervous system, causing movement disorders, psychosis, depression, anxiety, and intellectual disability/developmental delay. HCUNA brought in Benjamin Goodlett, PhD, to present on some of the cognitive, social, and emotional impacts that HCU can have on individuals, families, and relationships.
There is a high variance in the presentation of HCU. People may present all of the aforementioned symptoms, or only one. This can be largely in part by age of diagnosis/age when the homocysteine levels begin to be well controlled. Homocysteine levels from birth until age four specifically seem to be particularly important. Good control of homocysteine levels can potentially lead to avoidance of any clinical sequelae.
As described at length by HCU’s President Margie McGlynn, there are other treatment options on the horizon. To learn more about current research click here. To view all active clinical trials (including a natural history study!) for HCU go to Clinicaltrials.gov and search homocystinuria.
Resources:
Food tracking apps/sites: Calorie King, My Plate, Lose It, and My Fitness Pal.
Next Step –This organization is a twist on a traditional summer camp for young adults. Amidst the fun and games there is a conference component that helps people transitioning into adulthood with chronic illness feel more prepared and know what to expect. They also have a community that provides support and are able to talk with others who have handled similar challenges and can provide advice. The “campfrences” are free to attend.
The HCU Network America: This organization can connect you to countless resources. Through them, you can connect with other families, learn how to get reimbursed for medical foods, get informed about general guidelines for managing HCU, keep up to date on advancements in research and therapies in development and so much more.
