Eighty-four children with steroid-responsive nephrotic syndrome who had been shown to have, or were believed to have, minimal change histology were investigated to study the relationship between steroid-responsive nephrotic syndrome and allergy. They were found to have a greater incidence of the standard atopic disorders--asthma, eczema, recurrent urticaria, and hay fever. Their 1st-degree relatives had an increased incidence of these atopic disorders too. A nasal discharge was a frequent precursor or an accompaniment of nephrotic syndrome, but an overt atrophic disorder at the same time was rare. Such disorders, related to relapse, occurred in only 5 children; in none was it a consistent or recurrent happening at the time of each relapse. No example of pollen hypersensitivity nephrotic syndrome was found, and no particular allergen could be identified with certainty as responsible for a child's nephrotic syndrome. No association was found between the time of relapse and the season of the year, or the season in which the child was born. Children with nephrotic syndrome had a greater incidence of positive skin tests to common antigens, the comparative frequency of positive reactions to different antigens being similar to that found in children with asthma, although the total frequency was about half that of children with asthma. Despite the increased incidence of clinical features of atopy, measures to reduce the frequency of relapse of nephrotic syndrome by allergen avoidance, the use of sodium cromoglycate, and the use of a new oral antiallergic drug were unsuccessful.
We can collect and store DNA samples indefinitely, until we have enough to start the active research. Once we have samples from enough dogs, we analyse their DNA with about 170,000 different markers located along the DNA, to hopefully identify regions of the DNA that are similar in the cases and different in the controls; such a region is very likely to harbour the causal mutation. The dog’s genome consists of around two and a half thousand million ( x 109) nucleotides of DNA. If each nucleotide was 1mm long the canine genome would stretch from Land’s End to John O’Groats and back again. A mutation that is responsible for an inherited disease can be anywhere in the DNA and can be as small as a single incorrect nucleotide, so pinpointing a disease-associated mutation can be quite a challenge. Once we have identified a region (called the ‘critical region’) of the DNA that contains a mutation (equivalent to a one or two mile stretch of road on the journey from Land’s End to John O’Groats and back) we ‘zoom in’ on that region and sequence some or all of the DNA within the region, nucleotide by nucleotide, until we identify the mutation that is causing the disease we are investigating. Once we have identified the mutation and confirmed we have the correct mutation, by analysing the DNA from a large number of cases and controls, we develop a DNA test that is offered to the public by our DNA testing facility.
Follow-up appointments will be very important and absolutely necessary with a diagnosis of steroid-responsive meningitis-arteritis. Your veterinarian will determine the schedule of the return visits which will depend on how well your furry family member responds to the treatment. The follow-up will mean repeat blood tests and analysis of the CSF until the veterinarian can see that the markers have returned to normal. This could mean appointments every 4 to 6 weeks for several months. It is imperative that you keep the appointments and do not discontinue the medication even though you may think your dog is feeling better. It should be noted that many pets will need a prescription for gastroprotectants; if you see any side effects from the long-term therapy such as blood in the stool or vomiting, or if you are concerned in any way with your pet’s health, contact the clinic without delay. With SRMA there is a potential for relapse, meaning that continued contact with your veterinarian will be recommended.