can kids be diagnosed with down syndrome after one year even if they seemed fine before?

Question

i have only seen information on babies diagnosed when still in womb or newborn.

Answer 1

There is virtually no literature describing Down's syndrome children who have autistic features. Yet everyone who runs a Down's syndrome clinic occasionally sees a child of this type. This paper discusses an approach to the diagnosis and treatment of such a youngster.
Down's syndrome occurs in of between 1.0-1.2/1000 live births (Hook, 1982) while the autistic syndrome occurs between .4-.5/1000 live births (Torrey et at. 1975). Thus both Down's syndrome and the autistic syndrome are among the more common forms of mental handicaps seen in children.
One of the important questions on evaluating a child is to try and determine whether both disease entities have occurred coincidentally in this child or whether this child's autistic symptoms stem from an unusual effect of the addition of an extra twenty-first chromosome to the child's cells. One example of the double diagnosis occurs in Down's syndrome children who develop the infantile spasms syndrome associated with hypsarrhythmia. Patients, Down's or otherwise, who develop infantile spasms are often left with autistic features.
Clinical Delineation of a Child with Both Syndromes
To start with, it is necessary to define a Down's syndrome child with autistic features. Such a child can be diagnosed if the child, in addition to having a Trisomy 21 chromosomal karyotype (or one of the other chromosomal variants that result in the phenotype of Down's syndrome), the child also has two or more of the following disturbances:

Significant disturbance of social relatedness to parents and peers, with poor eye contact and a sense of "aloneness."
Repetitive routines such as lining up objects and insisting on the sameness of certain clothes or certain foods or certain spaces between objects at the time of eating, etc. These children also may have a fascination with spinning objects such as wheels of toy cars or records, bizarre attachments to certain objects such as stripes, pins, pieces of plastic toys.
Unusual, inconstant, sensory responsiveness. This can be seen in children who may appear deaf in one minute and overly sensitive to sound at another. Another example is a child who often shrinks from a touch but sometimes enjoys being tickled very forcefully.
A child who, in spite of his general level of retardation, has an islet of special ability at a completely different level that other levels of mental functioning. These skills may be in music, art, jigsaw puzzles or other visual spatial skills.
Evaluating autistic features in a Down's syndrome child can be quite difficult. If the child, for example, appears not to be hearing well, it may not be due to an autistic feature but may be due to otitis media (middle ear infection) a common problem seen in Down's syndrome children. A child who is irritable, withdrawn, with poor eye contact may be a child who is developing a hidden infection such as in the bladder, the middle ear or other infectious more commonly seen in a Down's syndrome child. Thus the diagnosis of autistic features should only be made if it is a consistent pattern over a considerable period of time where any infectious or other etiologies have carefully ruled out.
Medical Evaluation
Assuming that the diagnosis has been made of a Down's syndrome child with autistic features, then a medical evaluation is indicated. The autistic syndrome is not a single disease but a syndrome of many different etiologies.
Elevation of the uric acid both in the blood and in the urine of Down's syndrome patients has been an area under study for a long time (Pueschel, 1982). There have been many articles on the subject, a number puzzling over the fact that the hyperuricenna seen in Down's syndrome is less likely to result in gouty arthritis than in other individuals. Recently, using recombinant DNA techniques it has been determined that two of the genes involved in purine biosynthesis, phosphoribosyl-glycina-mide synthetase (PRGS) and phosphofructokinase (PFKL) are located on the 21st chromosome (Smith and Warren, 1985). It is much too early to know if these genes are the ones responsible for purine over-production in Down's syndrome, whether there also are modifying genes etc.
Three enzymes — 5-phosphoribosyt-l-pyrophosphate (PRPP synthetase), inosinate dehydrogenase and adenyl-osuccinate lyase — are enzymes in the purine pathway known to be abnormal in one of more autistic children. Some of these enzyme errors have experimental treatments available.
Thus, in evaluating a Down's child with autistic features, a uric acid clearance may be valuable. Even if it is not possible to pin down the exact gene or enzyme involved in a child, if the child is a purine overexcretor then dietary measures reducing purines or allopurinol can be tried in an effort to diminish autistic features. There are no double blind studies showing that these treatments are of value. In one 10-year-old boy with Trisomy 21 in my practice, such a diet and allopurinol appeared to make a difference in the child's attention span and ability to learn. It may or may not be coincidence that the child's clinical picture improved on the diet and allopurinol and deteriorated during two crossover periods off the diet and on placebo.

Lactic Acidosis in Down's Syndrome and the Autistic Syndrome
Lactic acidosis or hyperlactatemia without acidosis in a child indicates some abnormality in the utilization of sugar, which increases the rate of lactate production relative to lactate utilization. There is a paper in the literature describing lactic acidosis in a Down's syndrome child (Hartman et al. 1962). In my practice, there was a 3-year-old boy with Trisomy 21 who had a very poor attention span and a number of autistic features. The child was found to have lactic acidosis on repeated testing. Studies are currently underway in attempts to find, if possible, which enzyme is involved in the carbohydrate pathway in this child. Placed on a low carbohydrate diet and thiamin, the child's attention span and language showed marked improvement, with some evidence of deterioration or plateauing during two crossover periods. Again, no double blind studies have been done to confirm these results and, since a specific enzyme has not even been identified in this child, these results are most preliminary.

Down's syndrome children like other individuals have psychiatric symptoms. They can appear autistic or become anxious, depressed, anorexic or psychotic (Keegan et al. 1974; Semansky and Betelman 1984). The solution to helping children lies in thinking of them as individuals who also happen to have Down's syndrome and attacking the problem on an individual basis using individual medical therapy as appropriate. For the Down's syndrome child with autistic features, individual evaluation is particularly important.
We have the power to enhance the quality of life and the future of Down's syndrome individuals if we treat them with the care and attention each child deserves.

Answer 2

down's syndrome is a genetic disorder, which means a baby has it at conception. It is normally detected at birth or pre-birth because it has distinguishing characteristics. However, if a child lacks those characteristics, and has an extremely mild case, it may take a while to diagnose. Since it is a genetic disorder, doing a genetic profile gives a definitive diagnosis.

Answer 3

Yes they almost didn’t diagnose my son with it. In fact the nurses and Dr’s argued about it. The Dr Thought he didn’t have it and nurses thought he did. An hour before we got positive results he said that he does not think he has it and it is just a pre-caution. Well he does. Some people say cant you tell by looking, the answer was no. Some come out with the features but our son did not.

Answer 4

Babies with downs will be diagnosed at birth. There are very distinctive physical characteristics that will promp a dr to run a genetic test on the baby.

Answer 5

My brother was diagnosed a little after, I don't think it was a year though. You must also remember there are levels of severity. My mom figured it out before the doctor.

Answer 6

Downs Syndrome AKA Trisomy 21 is a genetic defect therefore it can be detected at any time using genetic testing. If you suspect your child has it, get them tested ASAP. It won't change anything, but at least you will know early and get them involved in Early Intervention.

Answer 7

Yes, unfortunately sometimes it is missed.... and it takes a little while to diagnose it.
However, it is 99% of the time diagnosed shortly after birth.. if not before.

Answer 8

Yes they can tell. Blood test will conferm. They are missing a gene. There are different forms of it some are milder than others. My Nephew is like that ... He can't talk. He never learned how...

Answer 9

Yes, it does happen. Sometimes the physical symptoms are mild and it can only accurately be detected with a karyotype.

Answer 10

There is something called mosiac down syndrome. a variety of down's but not as severe. Maybe that is it.

Answer 11

Yes, but unlikely as modern doctors will always pick up on it early.