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Accepted 30 January 1997 OBJECTIVE—To evaluate the efficiency of the screening programme for congenital hypothyroidism in Scotland and to determine the outcome in the cohort of children with positive testing for thyroid stimulating hormone (TSH). DESIGN—Establishment of comprehensive database for all Scottish infants with high TSH, detected on Guthrie screening. SUBJECTS—344 infants born between August 1979 and December 1993 with TSH greater than 40 mU/l on initial Guthrie, or 15-40 mU/l on repeat Guthrie. MAIN OUTCOME MEASURES—Ages at time of: (a) Guthrie collection, (b) notification of positive result by laboratory, and (c) start of treatment; audit of late diagnosis/missed cases; categorisation of positive cases into definite and probable congenital hypothyroidism, transient TSH elevation, and uncertain status; educational status of children with definite and probable congenital hypothyroidism. RESULTS—344 positive cases were categorised as having definite (224) and probable (11) congenital hypothyroidism, transient TSH elevation (88), and status uncertain (21). The overall incidence of definite/probable congenital hypothyroidism was 1 in 4400 live births. For the definite/probable groups median age of Guthrie collection was consistently between 6 and 7 days from 1983 onwards but for the whole cohort was later than 10 days in 10.5%. Median age of notification fell from 14days in 1980 to 11 days in 1993. Median age of starting treatment ranged between 11 and 15 days from 1983 onwards. Treatment was delayed in four cases, three due to failed or late Guthrie card submission. Of 149 children with definite/probable congenital hypothyroidism who were of school age, educational status was ascertained in 139 (93%). Only two children (1.4%) were attending special school, one of whom was known to have mild hypothyroidism. Sixteen children (11.5%) were receiving extra help in mainstream education compared with 18% of control children in the Scottish very low birth weight study. CONCLUSION—The current screening programme is working well, but efficiency could be increased by earlier and more reliable Guthrie collection. A substantial proportion of children picked up on the screening programme have a transient rise in TSH rather than true congenital hypothyroidism. The incidence of special education and learning support in Scottish children with congenital hypothyroidism appears to be no different to that of the general population.

We investigated the incidence of congenital malformation in all infants with raised thyroid-stimulating hormone (TSH) levels on neonatal screening in Scotland between August 1979 and December 1993. Of 344 infants with elevated TSH, 31 (9%) had one or more malformations: 12 cardiac 15 noncardiac, and 16 dysmorphic syndromes (including 5 with Down syndrome). Criteria were devised to distinguish between definite or probable congenital hypothyroidism and transient TSH elevation. Congenital hypothyroidism was considered definite in 224 (65.1%) infants and probable in 11 (3.2%). Eighty-eight (25.6%) infants had transient TSH elevation, whereas thyroid status was uncertain in 21 (6.1%). In the definite group 12 (5.4%) infants had one or more malformations compared with 13 (14.8%) in the transient group. Cardiac malformation, noncardiac malformation, dysmorphic syndromes, and "sickness" were much more frequent in the transient compared with the definite group: 5.7% versus 1.8%, 8.0% versus 1.8%, 6.8% versus 2.7%, and 37.5% versus 7.1%, respectively. The incidence of congenital malformation in bonafide congenital hypothyroidism is lower than has been previously reported. The high incidence of congenital malformation associated with transient TSH elevation indicates the need to reevaluate the diagnosis of hypothyroidism in all infants with TSH elevation and concurrent illness or malformation.

A paper radioimmunosorbent test (PRIST) was shown to be sensitive and reproducible when used with excretory/secretory antigen of Toxocara canis second stage larvae. Whatman No. 50 filter paper (5 mm discs) gave the most consistent and clear results with antigen at a concentration of 100 micrograms/ml, and could be stored for up to 3 weeks in vacuo at -70 degrees C. Antigen coated discs were incubated with test sera at 1:10 dilution for 3 h at room temperature (21 degrees C), reacted with [125I]anti-human IgG for 1 h and counts determined in a gamma counter. Sera from patients with fascioliasis, taeniasis, schistosomiasis, oxyuriasis, trichinellosis and ancyclostomiasis gave counts similar to cord serum controls. Sera from patients with ascariasis gave counts of up to twice as great as controls, but sera from patients with toxicariasis produced counts of 7,000-13,000, a 4-6-fold increase.

In vitro maintained second stage Toxocara canis larvae do not bind antiserum raised to their excretions and secretions (ES) at 37 degrees C as detected by indirect fluorescence. However, when these larvae were incubated at 2 degrees C under the same conditions intense fluorescence on the whole outer surface was observed. This fluorescence remained as long as the larvae were maintained at 2 degrees C. When these larvae were reincubated at 37 degrees C a gradual loss of fluorescence along their outer surfaces occurred. This loss was complete after 3 h. Larvae which were preincubated in antimetabolites at 37 degrees C exhibited intense fluorescence on their outer surfaces as did those incubated at 2 degrees C with antimetabolites. It is concluded that antigens present in ES occur along the whole length of the larval outer surface and turn over at 37 degrees C. This turnover occurs along the whole outer surface and is metabolically dependent. Should this occur in vivo it could afford the parasite with a mechanism for evasion of the immune response.

The efficiency of isolation of salmonellas from 412 seagull intestines and 247 polluted water samples was compared using three formulations of Rappaport's medium (RV, RV-soya and R25). A modification of RV medium (RV-soya) was shown to be the most efficient of the three media and it was shown that the duration of incubation of this medium could be restricted to 24 h. Inoculation ratios were compared for RV and RV-soya and 1:100 was shown to be significantly better than 1:20. It is concluded that RV-soya is at least as efficient as the standard RV medium and its use can therefore be recommended.

Male mice, strain C57 black, were infected with Toxocara canis by a single intragastric dose of 1500 infective eggs. The eyes were studied at sequential time periods after infection (6 to 63 days) by conventional microscopic techniques, and the histological characteristics of the inflammatory response were recorded. In the majority of animals the disease was unilateral. Twenty-six larvae were found in the retina, in the retinal vessels, and in the subretinal space in 20 eyes, while in 29 eyes there were inflammatory changes which were not related to the presence of intact or fragmented larval forms. The inflammatory reaction began as a polymorphonuclear response but after day 13 became a granulomatous reaction. This suggests that the inflammatory phenomenon may be propagated by the secreted surface antigens in the absence of the living or dead larvae.

The serotype distribution of 3631 strains of Streptococcus pneumoniae, isolated from various specimens obtained from patients was determined by coagglutination and included serotyping within a total of 13 serogroups. The results of serotyping of isolates from Scotland demonstrated that the new 23-valent pneumococcal vaccine includes serotypes which accounted for 91% strains associated with systemic disease and 79% strains isolated from other anatomical sites. Altogether, 114 strains (3.1%) were not typable because they did not possess a type-specific capsule; these were commonly isolated from eyes (12%).

SUMMARYSeven different flotation fluids were assessed for their efficiency in recovering Toxocara canis ova from artificially seeded soil samples. Using the most efficient (a saturated solution of magnesium sulphate plus 5 % potassium iodide) 25 g amounts of 234 environmental soil samples were examined for the presence of Toxocara spp. and Toxascaris ova. Twenty-six samples (11·1 %) yielded ova of one or other species. There was no discernible pattern of distribution of positives with relation to the source of the samples. The maximum number of ova recovered in any one sample was 19. All the ova recovered from the environment were considered viable and potentially infective.