METHODS: This was a prospective, cross-sectional study on spina bifida children aged 5-20 years, attending the paediatric spina bifida clinics of Universiti Kebangsaan Malaysia Medical Centre Kuala Lumpur and Hospital Tuanku Jaanku Seremban. Scores were obtained using the validated disease specific Parkin QOL questionnaire. Univariate and multivariate analysis were used to investigate factors that were determinants for these outcomes. Results were expressed as beta coefficient and 95% confidence intervals (95%CI).
RESULTS: A total of 54 children and adolescents aged between 5-20 years completed the questionnaires. Presence of neurogenic bowel (p=0.003), neurogenic bladder (p=0.041), shunt (p=0.044), non-ambulators (p=0.007) and being the only child in the family (p=0.037) were associated with lower QOL scores. Multivariate analysis showed presence of neurogenic bowel (β=0.375, 95%CI: 0.00, 0.15) and being the only child in the family (β=0.250, 95%CI: 0.04, 0.17) explained 22.1% of the variance in the QOL mean percentage scores.
CONCLUSION: Being a single child in the family was the only socio-demographic variable associated with lower QOL scores. Although several clinical factors appeared to contribute significantly to QOL in spina bifida children, the presence of neurogenic bowel had the greatest impact.
OBJECTIVE: To determine the prevalence and potential risk factors of vitamin D deficiency and insufficiency among Malaysian children with spina bifida.
SETTING: Four Malaysian tertiary hospitals.
METHODS: Children with spina bifida were assessed for potential demographic, disease severity and lifestyle risk factors for vitamin D deficiency and insufficiency. Blood for 25-hydroxy vitamin D (25(OH)D) was taken. Vitamin D deficiency was defined as 25(OH)D levels ≤ 37.5 nmol/L and insufficiency as 37.6-50 nmol/L.
RESULTS: Eighty children aged 2-18 years (42 males) participated in the study. Vitamin D levels ranged from 14 to 105 nmol/L (mean 52.8, SD 19.1). Vitamin D deficiency was identified in 18 (22.5%) and insufficiency in 26 (32.5%) children. Logistic regression analysis showed that skin exposure to sunlight ≤ 21% body surface area (OR: 6.2, CI 1.7-22.9) and duration of sun exposure ≤ 35 min/day (OR: 4.0, CI 1.2-14.1) were significant risk factors for vitamin D deficiency and insufficiency, respectively.
CONCLUSIONS: Over half (55%) of Malaysian children with spina bifida seen in urban tertiary hospitals have vitamin D insufficiency and deficiency. Lifestyle sun exposure behaviours were risk factors for vitamin D deficiency and insufficiency.
OBJECTIVE: The aim of this study was to clone and express Hev b 3 and to obtain the immunologic active and soluble recombinant allergen for diagnosis of SB-associated latex allergy.
METHODS: A complementary DNA (cDNA) coding for Hev b 3 was amplified from RNA of fresh latex collected from Malaysian rubber trees (Hevea brasiliensis). PCR primers were designed according to sequences of internal peptide fragments of natural (n) Hev b 3. The 5'-end sequence was obtained by specific amplification of cDNA ends. The recombinant (r) Hev b 3 was produced in Escherichia coli as a 6xHis tagged protein. Immunoblotting and inhibition assays were performed to characterize the recombinant allergen.
RESULTS: An Hev b 3 cDNA clone of 922 bp encoding a protein of 204 amino acid residues corresponding to a molecular weight of 22.3 kd was obtained. In immunoblots 29/35, latex-allergic patients with SB revealed IgE binding to rHev b 3, as did 4 of 15 of the latex-sensitized group. The presence of all IgE epitopes on rHev b 3 was shown by its ability to abolish all IgE binding to nHev b 3. Hev b 3 is related to Hev b 1 by a sequence identity of 47%. Cross-reactivity between these 2 latex allergens was illustrated by the large extent of inhibition of IgE binding to nHev b 1 by rHev b 3.
CONCLUSION: rHev b 3 constitutes a suitable in vitro reagent for the diagnosis of latex allergy in patients with SB. The determination of the full sequence of Hev b 3 and the production of the recombinant allergen will allow the epitope mapping and improve diagnostic reagents for latex allergy.
OBJECTIVE: We have conducted a multicenter clinical skin testing study to document the safety and diagnostic sensitivity and specificity of a candidate Hevea brasiliensis nonammoniated latex (NAL) extract. These data are intended to support the licensing of this reagent for the diagnosis of latex allergy in high-risk populations.
METHODS: Three hundred twenty-four subjects (304 adults and 20 children) were classified by their clinical history as having latex allergy (LA group, 124 adults and 10 children) or having no latex allergy (NLA group, 180 adults and 10 children). All subjects provided blood samples and then received sequential puncture skin tests (PSTs) at 1, 100, or 1000 microg/mL protein with a bifurcated needle and NAL (Greer Laboratories) from Malaysian Hevea brasiliensis (clone 600) sap. A 2-stage glove provocation test was used to clarify latex allergy status of individuals with positive history/negative PST result and negative history/positive PST result mismatches.
RESULTS: Twenty-four subjects (15%) originally designated as having LA on the basis of their initial clinical history were reclassified to the NLA group on the basis of a negative glove provocation test result. Of the 134 subjects with LA, 54 (40%) were highly sensitive to latex, with a positive PST result at 1 microg/mL NAL. The Greer NAL reagent produced a positive PST rate (sensitivity) of 95% and 99% in subjects with LA at 100 microg/mL and 1 mg/mL, respectively. The negative PST rate (specificity) in 190 subjects with a negative history with the NAL extract at 100 microg/mL and 1 mg/mL, was 100% and 96%, respectively. Immediately after the PST, mild systemic reactions (mainly pruritus) were recorded in 16.1 % of the adults in the LA group and 4.4% of the adults in the NLA group. No reactions required treatment with epinephrine. Only mild delayed reactions were observed in 9.6% (LA group) and 2.8% (NLA group) of subjects 24 to 48 hours after PST. Mean wheal and erythema diameters measured in the 10 children in the LA group with spina bifida at 100 microg/mL and 1 mg/mL were similar to those observed in the adults in the LA group, suggesting that children are not at increased risk for systemic reactions compared with adults.
CONCLUSIONS: A suggestive clinical history is necessary but not sufficient for a definitive diagnosis of IgE-dependent latex allergy. These data support the safety and diagnostic efficacy of the Greer NAL, skin test reagent at 100 micro/mL and 1 mg/mL for confirmatory PSTs.
OBJECTIVE: To evaluate the purified latex allergens and to demonstrate specific IgE antibody in the sera of health care workers and spina bifida patients with clinical latex allergy.
METHODS: Two radioallergosorbent and an enzyme-linked immunosorbent assay (ELISA) using latex proteins Hev b 1, 2, 3, 4, 6 and 7 along with two glove extracts and Malaysian nonammoniated latex (MNA) were evaluated to demonstrate IgE in the sera of health care workers and spina bifida with latex allergy and controls with no history of latex allergy.
RESULTS: ELISA using the purified latex allergens demonstrated specific IgE in 32-65% health care workers and 54-100% of spina bifida patients with latex allergy. The corresponding figures for RAST were 13-48 and 23-85 for RAST-1 and 19-61 and 36-57 for RAST-2. These results were comparable with the results obtained with glove extracts and crude rubber latex proteins.
CONCLUSIONS: When used simultaneously, latex proteins Hev b 2 and Hev b 7 reacted significantly with specific serum IgE in 80% of health care workers and 92% of spina bifida patients with latex allergy by ELISA technique, while this combination gave lower positivity when the RASTs were used. By the addition of Hev b 3, specific IgE was detected in all spina bifida patients with latex allergy. Both RASTs failed to show specific IgE in the control subjects, while the ELISA showed significant latex-specific IgE in 22% of controls.