Diagnosis in Children
For the most part ME/CFS can only be diagnosed in adolescents and older individuals. Children below the age of 8 or 9 do not have the symptom pattern of adolescents past puberty. If the onset of the disease occurs during adolescence, the most common time of onset, the pattern is similar to that of adults. Pediatric criteria have been developed5,6.
The onset is usually acute with an illness resembling mononucleosis, but unlike normal mono, it does not resolve in two to three weeks. Instead, the exhaustion, headache, muscle and joint pain, sore throat and lymph node pain become chronic. Exertion, even as seemingly minor as getting on a school bus may trigger a relapse causing the child to have to spend prolonged periods in bed. But not all children describe post-exertional malaise7. In general, the more severe the symptoms are in the first six months, the less likely to be resolution of the illness over time8. It has been my belief, although never proven in clinical studies, that an adolescent who spent the first three months in bed due to ME/CFS will still be ill at age 35, even though they may have been almost well in the years in between.
Of the many problems here, of course, is that no one has ever studied and published these issues in adolescents. It is impossible to predict at the onset of the disease if a teen has a standard viral infection or the beginning of a severe course of ME/CFS. In general, ME/CFS is a post-infectious phenomenon. The other great problem is that there is no simple laboratory test that can identify the presence or the severity of ME/CFS. Essentially all of the symptoms are subjective, and cannot be measured without subjective bias. It is comparable to the severity of a migraine headache. Normally, when someone says they have a migraine headache, we take their word for it, as it cannot easily be proven. But for ME/CFS, medical providers are reluctant to take the adolescent’s word for the presence of the symptoms.
Instead, providers usually suggest that the symptoms are not that bad, and that some exercise or counseling can remove them. Counseling is useful if an adolescent is coping poorly, and mild exercise can be of use when someone with the illness is improving spontaneously. But too often it precipitates a relapse, which is why the IOM suggested the name Severe Exertion Intolerance Disease4.
There are minor differences between adolescent ME/CFS and the adult ME/CFS. One is that abdominal pain is more common5 while this symptom is not even a part of some adult symptom criteria3. In addition, facial flushing is more common in teens9. I recall once when walking down the street in Lyndonville, I saw a teen with bright red facial flushing. He became ill within one or two days and remained ill for years. I made the mistake once of calling this a rash, but it is not a rash, it is flushing – the same as an adult can have when taking niacin. In some of the early outbreaks, this flushing rash is also mentioned and considered a standard symptom, one that involves the autonomic nervous system, as this part of the nervous system controls the diameter of the blood vessels.
Onset Prior to Puberty
I have seen many children where the parent will state that the child became ill at age 3. What the parent means by this statement is that, in retrospect, they can say that they noticed problems starting at age 3, but not that the whole symptom pattern was present. They may have noticed that their child was sleeping more than usual, or that their child seemed to get sick with viral infections more often than healthy kids. Children at a young age do not understand the concept of tiredness, because this word can only be used in reference to a state of good energy. If someone has never had prolonged ‘good energy’ the word fatigue has no meaning.
However during adolescence the symptom pattern coalesces into that of ME/CFS, so that it becomes possible to say that ‘in retrospect’ the illness began in early childhood. The cognitive symptoms from age 3 to age 12 are indistinguishable from attention deficit disorder, and this is another area that has never been adequately studied.