Nico from Scotland
Nico is our first of two children and was born in June 2019 in Aberdeen; which is located in the Northeast of Scotland. The pregnancy and delivery were a breeze (although admittedly this is being written by his dad…) and we were discharged the same day. As all new parents we spent the next few weeks navigating our way, mostly by trial and error, through the psychological enema that is the first exposure to parenthood. Despite our initial lack of parenting aptitude, Nico seemed very healthy, was easily breastfed and showed no signs of having any issues.
I am of Dutch descent, my wife is Scottish and neither of us have any known family history of inherited genetic disorders, metabolic or otherwise. Although Nico was subject to the routine newborn heel prick, the concept that Nico could be diagnosed with anything of that nature never even crossed our minds. Our lives changed, however, when he was around two weeks old, and we received a call out of the blue from the lead consultant in paediatric inherited metabolic medicine working for the Scottish National Health Service (NHS). It was a very short, and rather traumatic call, informing us that analysis of samples of Nico’s blood had identified elevated levels of Methionine, was likely suffering from a rare condition known as Homocystinuria and that his untreated life expectancy would be around 35 years.
Unsurprisingly, we were completely naïve as to what HCU was and after the short phone call, spent an emotional few hours frantically researching the condition online which only exacerbated our sense of panic. We were invited for a visit to the local hospital the same day where we met with paediatric clinicians who were able to explain in more detail, and with greater clarity, what the situation was and what our immediate options were. Further blood samples were to be taken to confirm the analysis, and Nico was to be subject to a two-week course of folic acid and pyridoxine supplements to test whether his measured amino acid levels would drop accordingly.
Nico showed no biochemical response to pyridoxine, and he was officially diagnosed with classical Homocystinuria. We were asked to stop the treatment once this was confirmed and effectively switch his diet overnight from breastmilk to a specially formulated methionine-free formula (HCU Anamix Infant) as his measured levels were remaining very high. Clearly it was not straightforward making the switch given the rather bitter taste of the formula but thankfully his blood levels (which were being measured on a weekly basis) were showing a rapid response to the treatment.
Once the dust had settled following a manic month or so including more blood tests, the failed treatment phase, switch to medicated formula and multiple road-trips to the metabolic centre in Glasgow we gradually began to realise what his only long-term treatment option was: a low protein diet accompanied by specially formulated powdered milk / paste protein supplement that he would take prior to every mealtime. We discovered early on that Nico is incredibly sensitive to natural protein and so his natural protein intake was, and still is, limited to 4 grams per day. In essence this is almost a negligible amount of protein, and the result is that he cannot really eat anything natural above and beyond fruit, select vegetables and small snacks. This is unfortunate but from purely a treatment perspective it does simplify matters, particularly when instructing others as to his dietary requirements.
Both my wife and I work full time and so since the age of one Nico has been at childcare (and now school) five days a week from 8am-5pm. Given the rarity of the condition, my wife has spent many hours, with the help of literature provided by the health service, educating the childcare staff on his diet and treatment (emphasising that it is not an allergy as that would result in meal-time isolation from his peers). In addition to the low protein processed food that provides the bulk of his calories, Nico has always been happy to snack on low protein natural foods like fruit and certain vegetables.
We are very fortunate that Nico’s low protein food comes prescribed through the Scottish NHS, with items such as low protein pasta’s, sausage / burger equivalents, bread, egg replacement etc. sourced from various countries in Europe as well as the United Kingdom. His medicated protein paste is made by Nutricia (owned by Danone) in the Netherlands. Given my heritage we regularly travel to the Netherlands and one day I intend on asking if we could have a tour of the factory that is so important to us.
Throughout his life Nico has mostly been pretty good at eating his low protein food and protein supplement and from a very early age appeared to understand that he must be selective with his choice of food: often rejecting anything offered to him by non-family members whilst referring to his ‘special belly’. The only serious wobble we have had to date was when he was two (of course….) and he refused to touch his protein paste for three weeks. Although looking back it seems rather innocuous and just normal boundary testing behaviour of a typical two-year-old terror, at the time we were riddled with anxiety and dreaded the worst. Worried that he would become protein deficient, I ended up building a spreadsheet detailing methionine percentage as a function of total protein content for hundreds of food types to understand what natural protein we could feed him whilst keeping his methionine levels supressed (see chart 2 as an example). Thankfully it never came to that as he figured three weeks was sufficient torture time for his parents and gradually began to eat his paste again.
These days Nico is a very sociable, active child and understands the key aspects of his condition. He enjoys going to school and participates in activities like swimming, football (soccer), rugby and tennis. We take monthly blood samples at home (which usually requires a few bribes) and deliver them to the hospital for analysis. His height and weight are monitored, and his eyes are checked on an annual basis for any abnormalities. His blood levels have remained relatively stable since we started his treatment, and he has not displayed any of the symptoms associated with untreated HCU.
Nico has an uncomplicated approach to life with his only objective for each day to have as much fun as can be squeezed into 14 hours (often waking his sister and parents up in the early hours in order to get a head start on that daily goal….). When we travel, we bring a suitcase of food for him and when we go out to restaurants and / or parties we try and make something in advance that will be similar to whatever type of food others will be consuming. We have reached an agreement with his school that they will prepare three meals a week for him (for which we are very grateful) on the basis that we provide the raw ingredients. To date we have had no issues with any of these, clearly the increase in niche diets globally has raised individual awareness and understanding of the need for bespoke dietary requirements.
Our main challenges regarding his diet for the coming years will be ensuring we gradually introduce more varied and complex tasting food into his routine as his pallet evolves and hopefully allow him to get some satisfaction out of eating rather than seeing it as a necessary chore. Additionally, as he gets older, he will gain more responsibility for his own consumption, and it is probably only natural for us to worry about what decisions he chooses to make when he does get to that stage (as every parent probably does!). Interacting with other, similar aged, HCU patients as a teenager and beyond will hopefully help guide him as he makes the journey into adulthood.
Nico has a younger sister, Naomi, who was born in 2021 and does not suffer from Homocystinuria. She was subject to more focussed testing upon birth due to the high likelihood (25% chance) of having the condition and we were clearly delighted when the blood results returned negative. The moment was a little bittersweet though as the natural elation we felt knowing Naomi was in the clear was a subconscious acknowledgement, combined with some repressed guilt, of the impact the condition will have on Nico’s life.
The condition is very rare in Scotland as Nico is currently (we believe) only the third child to have had the condition diagnosed since it was added to the heel-prick screening list (we were very fortunate as HCU was only included a few years prior to his birth). When Nico was born, he was the second child in Scotland diagnosed with the condition and we were very grateful that the parents of the first child were willing to talk to us and discuss their experience and likewise we spoke with the parents of number three.
The community nurses, metabolic specialists and paediatric dieticians working for the NHS have been invaluable to us over the years, providing guidance and advice, ensuring all his supplies are delivered in a timely manner, monitoring his development and helping with numerous other tasks that have allowed us to maintain control of his condition. We have no contact with any other HCU patients in our area and joining networks such as HCU America will hopefully allow us (and eventually him) to engage with a large community of people in similar situations. Unfortunately, DNA testing was not able to identify all the mutations responsible for his HCU, but we still hope that alternative treatment methods become available in the future and, if so, we could potentially carry out further DNA tests to better understand (and possibly treat) his specific condition. We will keep a close eye on ongoing studies and research.
