Around 65% of primary immunodeficiencies are antibody deficiencies. Functional tests are useful tools to study B‐cell functions in vitro. However, no accepted guidelines for performing and evaluating functional tests have been issued yet. Here, we report our experience on the study of B‐cell functions in infancy and throughout childhood. We show that T‐independent stimulation with CpG measures proliferation and differentiation potential of memory B cells. Switched memory B cells respond better than IgM memory B cells. On the other hand, CD40L, a T‐dependent stimulus, does not induce plasma cell differentiation, but causes proliferation of naïve and memory B cells. During childhood, the production of plasmablasts in response to CpG increases with age mirroring the development of memory B cells. The response to CD40L does not change with age. In patients with selective IgA deficiency (SIgAD), we observed that switched memory B cells are reduced due to the absence of IgA memory B cells. In agreement, IgA plasma cells are not generated in response to CpG. Unexpectedly, B cells from SIgAD patients show a reduced proliferative response to CD40L. Our results demonstrate that functional tests are an important tool to assess the functions of the humoral immune system.

Knowledge on multiple interdependences between quality of life (QoL) and behavioural problems in relation to asthma severity and control is undetermined. The aims of the study were: (i) to assess the relationship of QoL and behavioural problems with asthma severity and control (ii) to predict children’s “abnormal/borderline” status with variation in QoL. For these purposes a multicenter case-control study on 47 Severe Asthma (SA) and 94 Moderate Asthma (MA) children was performed. The MIMIC approach was applied to investigate the effect of SA and non-controlled asthma (NC) on QoL and behavioural disorders. Logistic regression was used to estimate probabilities of having an “abnormal/borderline” status with variation in QoL. The MIMIC model showed that the magnitude of the effect of SA and NC was larger on QoL (β = −0.37 and β = −0.30, respectively) than on behavioural problems (β = 0.27). With regards to the probability of having a borderline status, in MA a QoL of 1 returned a probability of 0.81, whereas in SA a QoL of 1 returned a probability of 0.89. In conclusion, SA children are highly affected by impaired QoL and behavioural problems. The MIMIC model allowed us to obtain a comprehensive assessment of QoL and behavioural problems with asthma severity and control.

Vernal keratoconjunctivitis (VKC) is a severe disease with a prevalence of < 1 case out of 10,000 in Europe, which occurs mainly in pediatric age and is characterized by a severe and often bilateral chronic inflammation of the ocular surface. The diagnosis is generally confirmed by the finding at the ocular examination of conjunctival hyperemia, papillary hypertrophy in the tarsal conjunctiva, giant papillae, papillae in the limbus region. Aim of this review is to provide an updated overview on the disease focused on clinical grading system, searching papers published in the last decade on VKC in scientific databases. Currently there are no standardized criteria for diagnosis of VKC and there is no uniformity to define disease severity, which makes difficult to diagnose and treat the disease. Given the wide overlap of the symptoms of VKC with the allergic conjunctivitis, criteria of probable, possible or improbable diagnosis are needed, providing pediatricians with parameters useful for deciding whether to drive the patient to the ophthalmologist for diagnostic confirmation.

Several institutions propose responsive feeding (RF) as the caregivers’ relational standard when nurturing a child, from breast/formula feeding onwards. Previous systematic reviews (SRs) on caregivers’ feeding practices (CFPs) have included studies on populations from countries with different cultures, rates of malnutrition, and incomes, whereas this SR compares different CFPs only in healthy children (4–24 months) from industrialized countries. Clinical questions were about the influence of different CFPs on several important outcomes, namely growth, overweight/obesity, risk of choking, dental caries, type 2 diabetes (DM2), and hypertension. The literature review does not support any Baby Led Weaning’s or Baby-Led Introduction to SolidS’ (BLISS) positive influence on children’s weight–length gain, nor their preventive effect on future overweight/obesity. RF-CFPs can result in adequate weight gain and a lower incidence of overweight/obesity during the first two years of life, whereas restrictive styles and coercive styles, two kinds of non-RF in CF, can have a negative effect, favoring excess weight and lower weight, respectively. Choking risk: failure to supervise a child’s meals by an adult represents the most important risk factor; no cause–effect relation between BLW/BLISS/RF/NRCF and choking could be found. Risks of DM2, hypertension, and caries: different CFPs cannot be considered as a risky or preventive factor for developing these conditions later in life.

During the complementary feeding period, any nutritional deficiencies may negatively impact infant growth and neurodevelopment. A healthy diet containing all essential nutrients is strongly recommended by the WHO during infancy. Because vegetarian diets are becoming increasingly popular in many industrialized countries, some parents ask the pediatrician for a vegetarian diet, partially or entirely free of animal-source foods, for their children from an early age. This systematic review aims to evaluate the evidence on how vegetarian complementary feeding impacts infant growth, neurodevelopment, risk of wasted and/or stunted growth, overweight and obesity. The SR was registered with PROSPERO 2021 (CRD 42021273592). A comprehensive search strategy was adopted to search and find all relevant studies. For ethical reasons, there are no interventional studies assessing the impact of non-supplemented vegetarian/vegan diets on the physical and neurocognitive development of children, but there are numerous studies that have analyzed the effects of dietary deficiencies on individual nutrients. Based on current evidence, vegetarian and vegan diets during the complementary feeding period have not been shown to be safe, and the current best evidence suggests that the risk of critical micronutrient deficiencies or insufficiencies and growth retardation is high: they may result in significantly different outcomes in neuropsychological development and growth when compared with a healthy omnivorous diet such as the Mediterranean Diet. There are also no data documenting the protective effect of vegetarian or vegan diets against communicable diseases in children aged 6 months to 2–3 years.