Ioanna Loukou

Bone mass density and associated factors in cystic fibrosis patients of young age

Aim:  To investigate bone mineral status in young cystic fibrosis (CF) patients and determine risk factors related with the development of low bone mineral density (BMD).

Differentiating vocal cord dysfunction from asthma

Vocal cord dysfunction (VCD)-associated symptoms are not rare in pediatric patients. Dyspnea, wheezing, stridor, chest pain or tightness and throat discomfort are the most commonly encountered symptoms. They may occur either at rest or more commonly during exercise in patients with VCD, as well as in asthmatic subjects. The phase of respiration (inspiration rather than expiration), the location of the wheezing origin, the rapid resolution of symptoms, and the timing occurring in relation to exercise, when VCD is exercise induced, raise the suspicion of VCD in patients who may have been characterized as merely asthmatics and, most importantly, had not responded to the appropriate treatment. The gold standard method for the diagnosis of VCD is fiberoptic laryngoscopy, which may also identify concomitant laryngeal abnormalities other than VCD. However, as VCD is an intermittent phenomenon, the procedure should be performed while the patient is symptomatic. For this reason, challenges that induce VCD symptoms should be performed, such as exercise tests. Recently, for the evaluation of patients with exercise-induced VCD, continuous laryngoscopy during exercise (such as treadmill, bicycle ergometer, swimming) was used. A definite diagnosis of VCD is of importance, especially for those patients who have been erroneously characterized as asthmatics, without adequate response to treatment. In these cases, another therapeutic approach is necessary, which will depend on whether they suffer solely from VCD or from both conditions.

Does Vitamin D Deficiency Epidemic Parallel with Allergy and Asthma Epidemic

Vitamin D (VD) deficiency has re-emerged, after more than hundred years, as a public health problem worldwide. Asthma and allergic disorders constitute another major public health problem with studies having recorded increasing prevalences worldwide since the decade of the 60s. Most of the available experimental and epidemiologic evidence point towards a causal association between low levels of VD and the development of asthma and allergic disorders, and imply a role of VD deficiency on the currently high prevalences of asthma and allergic diseases. The proposed, but still largely hypothetical, underlying mechanism is that VD affects the programming of the fetus and it also has a central modulating role in immune functions involved in asthma and allergic disorders. However, the evidence is not yet clear, since there are studies which support that VD supplementation during pregnancy may promote the development of asthma and allergic disorders. More researches, and especially randomized clinical trials, are required in order to draw safe conclusions and define the role of VD in the prevention or even therapy of asthma and allergic disorders.

Role of vitamin D in cystic fibrosis and non-cystic fibrosis bronchiectasis

Bronchiectasis is usually classified as cystic fibrosis (CF) related or CF unrelated (non-CF); the latter is not considered an orphan disease any more, even in developed countries. Irrespective of the underlying etiology, bronchiectasis is the result of interaction between host, pathogens, and environment. Vitamin D is known to be involved in a wide spectrum of significant immunomodulatory effects such as down-regulation of pro-inflammatory cytokines and chemokines. Respiratory epithelial cells constitutively express 1α-hydroxylase leading to the local transformation of the inactive 25(OH)-vitamin D to the active 1,25(OH)2-vitamin D. The latter through its autocrine and paracrine functions up-regulates vitamin D dependent genes with important consequences in the local immunity of lungs. Despite the scarcity of direct evidence on the involvement of vitamin D deficiency states in the development of bronchiectasis in either CF or non-CF patients, it is reasonable to postulate that vitamin D may play some role in the pathogenesis of lung diseases and especially bronchiectasis. The potential contribution of vitamin D deficiency in the process of bronchiectasis is of particular clinical importance, taking into consideration the increasing prevalence of vitamin D deficiency worldwide and the significant morbidity of bronchiectasis. Given the well-established association of vitamin D deficiency with increased inflammation, and the indicative evidence for harmful consequences in lungs, it is intriguing to speculate that the administration of vitamin D supplementation could be a reasonable and cost effective supplementary therapeutic approach for children with non-CF bronchiectasis. Regarding CF patients, maybe in the future as more data become available, we have to re-evaluate our policy on the most appropriate dosage scheme for vitamin D.

Vitamin D and Cystic Fibrosis Lung Disease

Vitamin D has been increasingly recognized as being involved in a wide spectrum of biological actions, including significant immunomodulatory effects. The cystic fibrosis (CF) airways are characterized by dysregulated and disproportionately increased, in relation to the underlying bacterial stimuli, inflammatory responses. Vitamin D downregulates pro-inflammatory cytokines and chemokines that promote tissue destruction, and which are abundant in CF lungs. However, despite mounting evidence for a pathophysiological role of Vitamin D in CF airways inflammation, there are only a few clinical reports supporting a relevance of Vitamin D insufficiency with CF airways damage, and so it is early to assign an indisputable causal role to Vitamin D. The present review will examine the current literature regarding the association of Vitamin D status with CF lung disease, and comment on the therapeutic implications accruing from these relations.

Long-term intestinal obstruction sequelae and growth in children with cystic fibrosis operated for meconium ileus: expectancies and surprises

BACKGROUND/PURPOSE In the few studies on intestinal complications and growth of cystic fibrosis (CF) patients with a history of meconium ileus (MI), operated MI has not been investigated separately. We aimed to investigate the incidence of long-term intestinal obstruction sequelae [constipation, distal intestinal obstruction syndrome (DIOS)] and growth in CF patients operated for MI. METHODS Retrospective study (1989-2016) including operative diagnoses and procedures, constipation and DIOS events, yearly Body Mass Index (BMI) measurements. Outcomes were examined in subgroups operated for MI only and for MI with atresia and/or volvulus. RESULTS Of 49 patients followed-up for 15 (mean) years, 5 (10.2%) developed constipation and 14 (28.6%) DIOS. BMI was within normal percentiles in 53 patients over a 10-year follow-up. MI only and MI with atresia and/or volvulus did not differ in constipation and/or DIOS incidence (11/34 vs. 7/15, p=0.39) or in BMI (p=0.47). Cases with ileocecal valve resection (ICV-R) showed lower constipation and/or DIOS incidence than those without ICV-R (0/6 vs. 11/28, p=0.02) and no different BMI (p>0.05). CONCLUSIONS CF patients operated for MI were in long-term risk for constipation/DIOS; their growth was normal. Interestingly, underlying atresia/volvulus neither increased constipation/DIOS risk nor affected growth. Strikingly, ICV-R showed no constipation/DIOS risk and no impact on growth. TYPE OF STUDY Retrospective comparative study. LEVEL OF EVIDENCE III.

The Role of Sensitization to Allergen in Asthma Prediction and Prevention

The burden of asthma in childhood is considerable worldwide, although some populations are much more affected than others. Many attempts have been made by different investigators to identify the factors that could predict asthma development or persistence in childhood. In this review, the relation between atopic sensitization as an indicator of allergy and asthma in childhood will be discussed. Cross sectional studies, carried out in different countries, failed to show any firm correlation between asthma and atopic sensitization. Birth cohort mainly of infants at high risk for asthma and case–control studies showed that atopic sensitization was a risk factor for current asthma in children older than 6 years. In general, clear relations are observed mostly in affluent Western countries, whereas in less affluent countries, the picture is more heterogeneous. For the prediction of asthma development or persistence in school age children, other prerequisites should also be fulfilled such as family history of asthma and wheezing episodes at preschool age. Despite the conductance of different studies regarding the potential role of allergen avoidance for the primary prevention of childhood asthma, it does not seem that this approach is of benefit for primary prevention purposes. However, the identification of children at risk for asthma is of benefit as these subjects could be provided with the best management practices and with the appropriate secondary prevention measures.

Is obesity related to the lung function of non-asthmatic children?

Overweight and obesity are highly prevalent in developed and developing countries among children and adolescents. During the last two decades, it became evident that excess weight is adversely related to respiratory health in childhood and adolescence mainly in terms of asthma occurrence. Additionally, there is a mounting body of evidence that overweight/obesity may also affect lung function in non-asthmatic subjects. The aim of this review was to present and discuss the studies that investigated this issue in non-asthmatic children and adolescents. Only a few studies have evaluated the impact of excess weight on static volumes and their results point towards an inverse relationship between overweight/obesity and functional residual capacity. More studies have been conducted on the impact of excess weight on dynamic lung volumes with inconsistent, however, results. Nevertheless, a relatively consistent finding was that the ratio of forced expiratory volume in 1 s/forced vital capacity was significantly lower among overweight/obese children compared to their counterparts with normal weight. The underlying mechanisms of these observations have not been adequately elucidated but it is believed to result from complex interaction of mechanical, developmental, and metabolic causes. There is a need for more well-designed studies in order to clarify the impact of excess weight on lung function in non-asthmatic subjects, as well as to explore the contribution of factors such as duration and degree of obesity, and fat distribution. Despite the absence of conclusive data, there are still convincing evidence to be communicated to the children and their families as part of the arguments to encourage them to adopt a healthier lifestyle.

Crackles and Other Lung Sounds

Crackles are intermittent, nonmusical, and brief adventitious lung sounds that can be heard on inspiration and sometimes during expiration. They are classified as fine or coarse depending on their frequency and duration; fine crackles have high frequency and short duration, whereas coarse crackles have lower frequency and longer duration. They are generated when air is forced through abnormally narrowed respiratory passages. The study of lung sounds, in general, and crackles, in particular, has advanced rapidly in the last two decades, thanks to the contribution of evolving technology. Based on various methods of artificial intelligence, researchers have managed to effectively detect and analyze lung sound signals and characterize them objectively. Unfortunately, the diagnostic utility of these high-end methods in clinical settings is still limited. In this review we attempt to summarize what is known about crackles and, in addition, discuss in less detail some of the other less common adventitious lung sounds.

Asthma and Allergy “Epidemic” and the Role of Vitamin D Deficiency

The increase in asthma and allergies prevalence that has been recorded in many countries during the last decades, and the reemergence of vitamin D (VD) deficiency in many populations worldwide, renders fairly plausible the assumption of an underlying association between these two conditions and justifies the research effort invented in this issue. Indeed, there is growing body of evidence from epidemiological, laboratory, and clinical studies, suggesting that such an association does exist. The hypothesis of low levels of VD leading to compromised fetal programming and impairment of various immune functions involved in asthma and allergic disorders, stands as the most credible explanation of this presumed association. However, the evidence is not yet definite and there are some conflicting results among studies. As a consequence, no safe conclusions can be drawn yet, and more research is required in order to fully clarify the involvement of VD deficiency in the pathogenesis of asthma and allergies, and decide if VD has a role to play in the prevention and therapy of these disorders.