Birth weight
Birth weight values of 195 patients were available for analysis. The highest standard deviation (SD=721) and the lowest mean birth weight (mean 2857,3g) referred to patients with PID (Fig.1). In addition, patients treated with immunoglobulin (PID Ig+therapy) were born with a little less mean birth weight (mean 2822,88g) and higher SD (SD=785,57) than PID patients without therapy (PID Ig -therapy; mean 2897,86; SD=648,56). 29,5% (n=18) of children with PID were born with weight under 2500g, while in the RRTI group only 6,25% (n=4, among 64 available data) and in the control group 2,86% (n=2, among 70 available data) of children had the same low weight score.
Birth length
Birth length values were collected from 170 patients. Children with PID had the lowest mean birth length (mean=50,8cm) and the highest standard deviation among all groups (SD=6,36); when dividing into groups with or without substitution of immunoglobulin, the highest SD (6,84) and the lowest mean birth length (h=50,61cm) related to PID Ig+therapy (Fig.2).
Weight during hospitalization
Weight during hospitalization data (patients were hospitalized at different ages) were available for all the patients. They were assigned to certain centiles, based on the Polish growth standards (Fig.3). Almost 20% of patients with PID (n=12) had weight under 3rd percentile, 7% (n=5) of the RRTI group. There were no statistically significant differences in weight centiles between these 2 groups (Pearson Chi^2 test, p=0,085). Relevantly more often weight under 3rd percentile affected children with PID Ig+therapy (n=11) than those without substitution (PID Ig-therapy, n=1), although there were no statistically significant differences between those groups (Pearson Chi^2 test p=0,138). A significant statistical difference was found between weight centiles of children with PID and control group (p=0,002).
Height during hospitalization
Height during hospitalization data were available as well for all the patients. They were classified to certain centiles according to both Polish (Fig.4) and WHO standards. According to Polish standards every fifth PID patient (n=12, 20%) and 10 RRTI patients (13%) were classified in the <3 centile compartment. In the 3-10 percentile interval there were 6 patients in the PID group (10%) and 4 in the RRTI group (5%). There were no statistical differences between height assigned to certain centiles of PID and RRTI group (p=0,09) with the Polish standards. According to WHO's, 11 patients (18%) from the PID group were situated below 3rd percentile of height, same with the z-score <-2SD (Fig. 5). Z-score <-2SD more frequently referred to the Ig+therapy PID patients (n=8) than to patients without substitution (n=3), although it wasn't statistically relevant (p=0,44). There was a statistically relevant difference between female and male height Z-score from the PID group (p=0,021). There were 6 girls with height between -2SD and -3SD z-score and 0 girls with height under -3SD z-score, while 3 boys with PID had height between -2SD and -3SD z-score and 2 had height under -3SD z-score. 8 patients (10,53%) from the RRTI group had their height below Z-score <-2SD. There were no statistically significant differences between PID and RRTI group in terms of height Z-score (p=0,7) or between PID and the control group both in the height centiles of Polish standards (p=0,06) and Z-score (p=0,1).
Based on data collected from all of the patients the BMIs were calculated and classified to certain nutritional status of Polish centile charts standards (Fig.6). Nutritional status was possible to define using centile charts for age 3-18 years old (PID n=43, RRTI n=52, control group n=35). It was within normal for most of the patients (PID-67,44%, n=29, RRTI-67,3%, n=35, control group-82,86%, n=29). 10 patients over 3 years old from the PID group were underweight (23,26%, 16,39% of all participants). In the RRTI group 6 patients over 3 years old were underweight (11,54%, 7,89% of all participants). 5 PID patients and 10 RRTI were diagnosed with overweight. Obesity was observed in one person in the RRTI group, whereas in the PID group no sign of obesity was found. Nevertheless, differences between these 2 groups weren't statistically significant (test Chi^2 Pearsona, p=0,4). The statistically significant difference was between the nutritional status of PID patients and the control group (p=0,018) (Fig.6).
BMI was also assessed using the z-score based on WHO standards for all participants (Fig.7). Z-score <-2 was detected among 5 people in PID group (8,2%), 3 of them had BMI <-3 z-score . Among these 5 people, 2 remained without immunoglobulin substitution by the time of study, the other 3 had such treatment. Three from that group were under 3 years old, so evaluation of nutritional status with Polish standards wasn't possible. One patient was diagnosed with ataxia-telangiectasia (z-score <-3), one with Nijmegen breakage syndrome (-3<z-score <-2), three had predominantly antibody deficiencies (n=2 z-score<-3; n=1 -3<z-score<-2) with no other already diagnosed conditions. Z-score between -1 and -2SD included 11 patients with PID (18%). 14 patients (22,95%) had a z-score between +1 and +2SD and only one patient (1,64%) had BMI >2SD.
In RRTI group 5 patients (6,58%) had Z-score <-2SD, 4 of them <-3SD, 9 patients (11,84%) had Z-score between -2SD and -1SD, 13 people (17,1%) 1SD<Z-score<2SD and 10 patients (13.16%)>2SD. There was no statistically relevant difference in z-score BMI between PID and control group (p=0,357), as well as between PID and RRTI (p=0,258).
There was no statistically relevant difference in nutritional status using Polish standards between PID patients with or without immunoglobulin substitution (p=0,087), although it's worth noting that underweight more frequently referred to Ig+therapy patients (n=9; 33,33%), than to Ig-therapy (n=1; 5,88%) (Fig. 8). No statistically relevant difference was found either in case of BMI Z-score (p=0,129).
Among 10 underweight patients from PID group (ages 3-20), 5 people had been diagnosed with ataxia-telangiectasia, 2 with Nijmegen breakage syndrome, 1 with Edwards syndrome, 1 with main classes immunoglobulin deficiency and 1 with C-1 esterase inhibitor and partial C4 component deficiency. Among patients under 3 years old, three with main classes immunoglobulin deficiency had BMI Z-score below -2SD.