More than 7,000 rare diseases are known, affecting more than 300 million people worldwide, and about 70% of them begin in childhood. A symptom that persists is obviously not the same thing as a rare disease, but it sometimes deserves a coordinated second opinion when the usual explanations no longer hold.
If a symptom persists in your child, or if the diagnostic path is still unclear, Noria Health Hub can arrange a full check-up or a second medical opinion in Brussels, with a report within 24 h, coordinate your care where needed across more than 40 medical pathways in 48 h, then, if your medical condition allows, arrange surgery within 7 days.
In children, some diagnostic delays have measurable consequences
Type 1 diabetes in children is the best documented example. It should be found on simple signs, unusual thirst, heavy urine output, weight loss. Too often it is found in ketoacidosis, that is, at the stage of the acute complication.
| What is measured | The result |
|---|---|
| Share of type 1 diabetes found in ketoacidosis, 13 countries, 59,000 children | 29.9%, lowest values in Sweden and Denmark |
| International range, 65 studies, 31 countries | 12.8% to 80% depending on the country |
| France, 1,299 children under 15 over 1 year | 43.9%, and 54.2% in the under-5s |
| Province of Parma, before and after an 8-year school campaign | 78% to 12.5% |
The Parma campaign was not about a complex programme. It was about a single sign, bedwetting returning in a child who had become dry, reported by 89% of parents. It is the best result-to-effort ratio in the file.
The same mechanism operates for rare disease. A European survey of 6,507 people and 1,675 rare diseases measures a mean diagnostic delay of 4.7 years. And the factor most strongly associated with delay is not the rarity of the disease, it is the fact that symptoms began in childhood or adolescence, with odds ratios of 3.11 and 4.79 respectively.
Neurodevelopment, the delay can run into years
| What is measured | The result |
|---|---|
| Global mean age at autism diagnosis, meta-analysis of 56 studies, 120,540 people | 60.5 months, that is 5 years |
| Median age at diagnosis in the United States, national network, 8-year-olds | 47 months, ranging from 36 to 69.5 months across sites |
| Median age at first attention disorder diagnosis in the United States | 7 years, with 1 child in 3 before age 6 |
| Mean age at autism diagnosis, girls against boys, national registry | 12.7 years against 9.5 years |
The last line says the essential. It is not that girls are less affected, it is that they are recognised later.
A recent result deserves to be known, because it contradicts what everyone has been taught. In an exhaustive Swedish birth cohort of 2,756,779 children, the boy-to-girl ratio for autism, calculated cumulatively to age 20, falls to 1.2. The famous 4 to 1 ratio is largely an artefact of the age at which diagnosis is made.
At the same time, what the screening tools are worth must be said. The most used autism screening questionnaire for 16 to 30 months has, in a Swedish cohort of 2,178 children, a sensitivity of 62.4% and a positive predictive value of 31.4%. In other words, about 2 positive screens in 3 are false alarms, and nearly 4 autistic children in 10 are not picked up. It is a signposting tool, not a test.
Routine child screening, a great deal of the evidence remains insufficient
The US Preventive Services Task Force assesses each screening item and assigns it a grade. Grade B means net benefit demonstrated. Grade I means insufficient evidence, which is not the same as useless. Here is the actual table.
| What is screened | Population | The grade |
|---|---|---|
| Depression | 12 to 18 | B, recommended |
| Anxiety | 8 to 18 | B, recommended |
| Vision, amblyopia and risk factors | 3 to 5, at least once | B, recommended |
| Autism, child with no concern expressed | 18 to 30 months | I, insufficient evidence |
| Lipid profile | Under 20 | I, insufficient evidence |
| Idiopathic scoliosis | 10 to 18 | I, insufficient evidence |
| Blood pressure | Children and adolescents | I, insufficient evidence |
| Speech and language delay | Under 5, no presenting concern | I, insufficient evidence |
Of 12 paediatric items assessed, 8 are graded I. It is the datum that most directly contradicts the idea of a comprehensive assessment of a healthy child.
An honest qualification is required. Other bodies recommend, for example, universal lipid screening between 9 and 11. They do not contradict the finding, they weight the absence of proven effect in adulthood differently. We quote the 2 positions because both of them exist.
Radiation, an exposure to be justified even more strictly in children
A child receives a higher dose for the same examination and is more sensitive to it. That is not a precautionary principle, it is measured.
| The study | What is measured | The result |
|---|---|---|
| British cohort, 178,604 patients under 22 | Leukaemia and brain tumour after CT | About 1 excess leukaemia and 1 excess brain tumour per 10,000 head CT scans in under-10s, over the following 10 years |
| Australian cohort, 10.9 million people, 680,211 exposed | Cancer incidence after childhood CT | Incidence rate ratio of 1.24, and +0.16 per additional scan |
| European study with individual dosimetry, 948,174 people, 9 countries | Haematological malignancies | For 10,000 children scanned today, 1 to 2 will develop an attributable malignancy within 12 years |
| American dosimetric analysis, 4.8 million child-years | Effect of a simple dose reduction | Bringing the highest-dose quarter of scans down to the median dose would avoid 43% of projected cancers |
The last line is the most useful in practice. Most of the avoidable risk lies not in the number of examinations but in the settings of the machine.
This work has attracted serious methodological criticism, on reverse causation, that is, children being scanned because they are already ill. The European study, with individual dosimetry and exclusion of the first 5 years of follow-up, partly answers that criticism. We will therefore not present this link as definitively established, nor will we dismiss it.
Imaging in a child with no symptoms, the risk of incidental findings
A meta-analysis of 7 studies covering 5,938 healthy children who underwent brain MRI finds 16.4% incidental findings. The breakdown matters more than the total. Intracranial cysts 10.2%, non-specific white matter hyperintensities 1.9%, Chiari malformation 0.8%, intracranial tumour 0.2%. A clinically significant finding concerns fewer than 1 child in 38.
The ratio between what is found and what is useful is therefore about 1 in 25 to 1 in 60. For the other 24 to 59, what remains is an image in a file, parental anxiety, and sometimes a 6-month check that calls for another.
Three situations where the test can do more harm than good
| The situation | What was measured | The result |
|---|---|---|
| Minor head injury, 42,412 children, 25 emergency departments | Share scanned and yield | 35.3% scanned, important injury in 0.9%, neurosurgery in 0.1%. About 1 scan in 5 was in a child from the very low risk group |
| Typical bronchiolitis, 265 infants | Yield of chest radiography | 133 children must be radiographed to find 1 image inconsistent with the diagnosis |
| Mild to moderate bronchiolitis, double-blind randomised trial, 213 infants | Effect of the oximeter reading, artificially raised by 3 points | Admission at 72 hours in 41% against 25%, with no difference in actual condition nor in return visits |
The third is the most striking. The same child, in the same condition, is admitted or sent home according to a displayed number. It is the clearest demonstration that a measurement is not neutral.
Antibiotics, avoiding prescriptions that serve no purpose
In the United States, about 30% of outpatient antibiotic prescriptions are estimated to be unnecessary, and for acute respiratory infections only half of prescriptions are justified. Across 15.4 million dispensations analysed, 23.2% were inappropriate and 28.5% were attached to no diagnostic code at all. This is not specific to paediatrics, but children are the most exposed population.
How long people wait
| Country | What is measured | The wait |
|---|---|---|
| France | Paediatrician appointment | Median of 8 days, mean of 22 days, 9th decile at 64 days |
| England | Children waiting for community health services | 49.5% wait more than 18 weeks, against 15% of adults. 44,066 children wait more than 52 weeks |
| England | Child and adolescent mental health | Median wait of 35 days for those who entered treatment, 179 days for those still waiting |
| England | Suspected autism assessments | Only 4.5% had a first appointment within the recommended 13 weeks |
The gap between 15% of adults and 49.5% of children beyond 18 weeks is the hardest figure in this table to justify. No medical reason explains it.
What the studies do not allow anyone to claim
We will not offer a comprehensive assessment to a healthy child, because 8 of the 12 paediatric screening items assessed are graded insufficient evidence and because imaging in an asymptomatic child has a useful yield below 1%.
You will not read here either that nothing should be done. The difference between comfort imaging and imaging on a presenting sign is measured. In an infant with a first seizure, brain MRI is abnormal in 58.2% of cases. The yield goes from under 1% to nearly 6 in 10, for the same machine. What changes everything is the question asked before the test.
In practice, if this concerns you
You set out your problem, your symptoms or your question. Reports, laboratory results and images already available can be studied before you arrive, so that the pathway is prepared. The aim is not to run every test as a matter of course, but to select those that can genuinely help confirm a hypothesis, rule out a risk or guide the decision. The results are brought together and the next steps are organised. Follow-up is then coordinated.
Have my child’s symptoms assessed
Need a medical opinion quickly? For a concern that does not call for emergency services, you can ask to speak to a doctor at any time through Noria Health Hub. This on-demand medical consultation is billed separately from the assessment pathway.
Further reading
The companion articles.
What” rel=”noopener” target=”_blank”>https://noriahealth.com/blog/what-a-health-assessment-can-actually-find/”>What a health assessment can actually find
How” rel=”noopener” target=”_blank”>https://noriahealth.com/blog/how-we-build-a-health-assessment/”>How we build a health assessment
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