Nasal nitric oxide and nitric oxide synthase expression in primary ciliary dyskinesia.

No study has evaluated the correlation between different expression of nitric oxide synthase (NOS) isoforms in nasal epithelial cells and nasal NO (nNO) level in primary ciliary dyskinesia (PCD). Gene expression of endothelial (NOS3) and inducible NOS (NOS2) and their correlation with nNO level, ciliary function and morphology were studied in patients with PCD or secondary ciliary dyskinesia (SCD). NOS3 gene polymorphisms were studied in blood leukocytes. A total of 212 subjects were studied (48 with PCD, 161 with SCD and three normal subjects). nNO level correlated with mean ciliary beat frequency (p = 0.044; r = 0.174). The lower the nNO level the higher was the percentage of immotile cilia (p<0.001; r = -0.375). A significant positive correlation between NOS2 gene expression and nNO levels was demonstrated in all children (p = 0.001; r = 0.428), and this correlation was confirmed in patients with PCD (p = 0.019; r = 0.484). NOS2 gene expression was lower in PCD than in SCD (p = 0.04). The NOS3 isoform correlated with missing central microtubules (p = 0.048; r = 0.447). nNO levels were higher in PCD subjects with the NOS3 thymidine 894 mutation, and this was associated with a higher ciliary beat frequency (p = 0.045). These results demonstrate a relationship between nNO level, NOS mRNA expression and ciliary beat frequency.

Simplified cell culture method for the diagnosis of atypical primary ciliary dyskinesia.

BACKGROUND: The diagnosis of primary ciliary dyskinesia (PCD) can be challenging, and it may be particularly difficult to distinguish primary ciliary disease from the secondary changes after infections. OBJECTIVES: The purpose of the study was to evaluate if nasal epithelial cells, obtained with nasal brushing instead of a biopsy, could be used in a culture system for the diagnosis of PCD in difficult cases. METHODS AND MAIN RESULTS: Ciliary motion analysis (CMA) and transmission electron microscopy (TEM) were performed on 59 subjects with persistent or recurrent pneumonia. These investigations allowed the diagnosis of PCD in 13 (22%) patients while the defect of the cilia was considered secondary to infections in 37 (63%) subjects. In the remaining nine (15%) patients the diagnostic evaluation with CMA and TEM remained inconclusive. Ciliogenesis in culture allowed the diagnosis of PCD in four of these patients, it was indicative of a secondary defect in two subjects, and it was not helpful in the remaining three patients. CONCLUSIONS: Culture of cells obtained with brushing of the nasal turbinate is not a perfect test, nevertheless it may offer diagnostic help in doubtful cases of PCD.

Bronchiectasis in children with recurrent pneumonia: an immunopathological damage associated with secondary ciliary dysmotility.

The aim of this study is to assess ciliary motion patterns in children with bronchiectasis unrelated to cystic fibrosis or primary ciliary dyskinesia. In 51 children with recurrent pneumonia, high resolution computed tomography (HRCT) was carried out to detect and score bronchiectasis. Moreover, ciliary ultrastructure, beat frequency and motion pattern were evaluated and compared to those observed in 30 healthy children. Bronchiectasis at HRCT was found in 31/51 children. Ciliary dysmotility was found in 20/31 children with bronchiectasis (64.5%). Overall, ciliary dysmotility was found in 39/51 patients (76.5%). Ciliary dysmotility showed a significant correlation with the HRCT score (p=0.02). Absent motion in some fields was found in 44/51 patients (86.3%) and this also showed significant correlation with the HRCT score (p=0.005). The specificity and sensitivity of ciliary dysmotility as an indicator of bronchiectasis was 74.3% and 83.3% respectively. The positive predictive value was 93.5%, and negative predictive value was 50%. Ciliary dysmotility, in children with recurrent airways infections, correlates with the presence and severity of bronchiectasis. Whether ciliary dysmotility is a cause or a consequence of anatomical lesion is a matter of speculation. Very likely there is an amplification and self-maintaining mechanism between the two events which may lead to more serious disease.

Diagnosing Sjögren-Larsson syndrome in a 7-year-old Moroccan boy.

Sjögren-Larsson syndrome (SLS) is an autosomal recessively inherited neurocutaneous disorder characterized by the triad of congenital ichthyosis, mental deficiency, and spastic diplegia or tetraplegia. Less common features are retinal changes, short stature, kyphoscoliosis, preterm birth, photophobia, reduction of visual acuity, seizures, and delayed speech. SLS is characterized by a genetic block in the oxidation of fatty alcohol to fatty acid because of deficient activity of fatty aldehyde dehydrogenase (FALDH), a component of the fatty alcohol: NAD oxidoreductase enzyme complex. As in other rare multisystem diseases, the diagnosis of SLS is often delayed. The definitive test for SLS is considered the measurement of FALDH or fatty alcohol: NAD oxidoreductase in cultured skin fibroblasts. Nevertheless, if specific FALDH activity test or DNA FALDH gene mutation tests are not available (as in our country), a reliable diagnosis of SLS is also possible when it is based on the matching of peculiar clinical, histologic and ultrastructural, laboratoristic, and imaging features. The simultaneous presence of cutaneous histologic features including hyperkeratosis, orthokeratosis, thickening of granular layer, abnormal lamellar inclusions in the cytoplasm of granular and horny cells (demonstrated by light and electron microscopy) in a child with ichthyosis, and typical neurologic abnormalities is highly suggestive of SLS. We describe the case of a young Moroccan boy presenting with ichthyosis, mental retardation, spastic diplegia, and peculiar skin histologic findings.

Nasal nitric oxide is low early in life: case study of two infants with primary ciliary dyskinesia.

Nasal nitric oxide levels are low in patients with primary ciliary dyskinesia, but it is not known whether this defect is already present in the first months of life. The current authors measured nasal nitric oxide in two infants with situs inversus and primary ciliary dyskinesia, diagnosed by electron microscopy at 4 and 6 months of age, and in five healthy control infants. Nasal nitric oxide values in the primary ciliary dyskinesia infants (85 and 115 parts per billion (ppb)) were markedly lower than in the healthy controls (mean: 295 ppb, range: 225-379 ppb). This is the first report to show that nasal nitric oxide values are already low in early life in primary ciliary dyskinesia children, supporting the hypothesis that a reduced production of nasal nitric oxide is an intrinsic feature of this disease. The current authors suggest that the nasal nitric oxide test may be a useful, noninvasive method for screening young children for primary ciliary dyskinesia in clinical practice.

"Cyst-like" structures within the ciliary shafts in children with bronchiectasis.

"Cyst-like" structures within the ciliary shafts were considered in four adults as a primary defect involved in the development of bronchiectasis. In this study, the presence and the primary or secondary nature of this abnormality were assessed in children with bronchiectasis. High resolution computed tomography (HRCT) and nasal biopsies for motion analysis and transmission electron microscopy (TEM) evaluation of cilia were obtained in 45 children with recurrent lower airway infections and abnormal chest radiography. HRCT disclosed bronchiectasis in 35 out of 45 (77.8%) children and cyst-like structures were demonstrated with TEM in 29 out of 45 (64.4%) patients. Cyst-like structures were constantly associated with other ultrastructural abnormalities commonly observed in chronic inflammation, and were found both in subjects with primary and with secondary ciliary dyskinesia. When considering only patients with bronchiectasis, a significant correlation between prevalence of cyst-like structures and the severity of bronchiectasis was demonstrated. Follow-up (2-22 months) of seven patients demonstrated that in the five children with secondary dyskinesia, the ultrastructural defect completely disappeared and there was a small reduction in the abnormality in the two patients with primary dyskinesia. In contrast to one previous report, the reversibility of the defect suggests its secondary origin, which is most likely related to chronic airway inflammation.

Primary ciliary dyskinesia: diagnosis in children with inconclusive ultrastructural evaluation.

The purpose of this study was to distinguish between acquired and genetically determined ciliary abnormalities in children with severe chronic respiratory diseases. Samples of nasal ciliated epithelium from 50 subjects (25 male, 25 female; age-range 2-19 years) with severe chronic respiratory diseases were examined using transmission electron microscopy (TEM). Based on TEM findings, patients were divided into two groups: A and B. Group A comprised 39 children with ciliary alterations compatible with a condition probably occurring secondary to chronic inflammation (alterations of peripheral pairs, swollen cilia, and compound cilia). The other 11 patients, Group B, exhibited a greater number of alterations of the central pair and dynein arms (p< 0.001), which were qualitatively similar to, but less numerous than, those observed in primary ciliary dyskinesia (PCD). In both groups, analysis of ciliary beat frequency and waveform was performed by phase contrast microscopy (PCM). All the children with a ciliary beat frequency of < 7 Hz were treated with daily physiotherapy and with antibiotics, as recommended for PCD, for a 6-month period. After this treatment, the children were reexamined by PCM. Almost 50% of the children from Group B (i.e. those with a small proportion of specific ultrastructural defects) showed permanence of low ciliary beat frequency. This was also observed in two children of Group A. These children were considered to be affected by PCD. Our study describes a method for the diagnosis of PCD in the absence of specific ultrastructural defects or when these defects are present in only a small proportion of the cilia.

CT-guided radiolabelled aerosol studies for assessing pulmonary impairment in children with bronchiectasis.

OBJECTIVE: To determine whether CT-guided mucociliary clearance studies allow differentiation between bronchiectasis associated with primary ciliary dyskinesia (PCD) and those unrelated to congenital or genetically transmitted defects. MATERIALS AND METHODS: Fifteen children aged 4-18 years with a CT diagnosis of bronchiectasis were included in the study. Six had PCD, while in nine cases no congenital disorder was demonstrated. RESULTS: CT showed bronchiectasis in 26 (29%) of 90 lung regions. Radiolabelled aerosol studies were conducted globally for each lung and on the regions affected by bronchiectasis. Global half-time of activity (t 1/2) values of patients with PCD were significantly higher (P < 0.001) than those with bronchiectasis unrelated to congenital disorders. Among the 26 lung regions in which CT demonstrated bronchiectasis, regional clearance was abnormal in 24 cases. Patients with PCD showed no statistically significant difference between regional and global t 1/2 values. Patients with bronchiectasis unrelated to congenital disorders showed significantly higher regional t 1/2 values in the affected regions with respect to the corresponding global pulmonary t 1/2 (P < 0.06). CONCLUSIONS: The combination of morphological CT information with functional data concerning the clearance of radiolabelled aerosol adds to our understanding of pulmonary impairment in children with bronchiectasis. In particular, regional studies allow the recognition of different mucociliary clearance patterns in bronchiectasis associated with PCD and those unrelated to congenital or genetically transmitted defects.

[Percutaneous renal biopsy in children: use of a fine needle]. / Biopsia renale percutanea in età pediatrica: uso di un ago sottile.

Percutaneous renal biopsies were performed on native kidneys in 40 children and adolescent, aged 1.7-13 (mean 6.7) years. Bleeding diatheses were excluded by the determination of Hb, blood platelets, PT, PTI and fibrinogen. Biopsies were performed under ultrasound imaging, using a semiautomated and thin needle (20 gauge in children with age under 5 years and 18 gauge for those over 5 years). All the patients were lightly sedated, except for 3 ones who received a general anesthesia. Diagnostically adequate tissue was retrieved in 38 of 40 biopsy procedures (95%). A macro-haematuria was observed with elimination of haematic coagula in 3 children (7.5%) and 24-h post-biopsy ultrasonography disciosed a small haematoma of the biopsied kidney in 2 one (5%). No mayor complications occurred. We conclude that the use of ultrasound imaging and a semiautomated needle is a safe and efficient method for performing renal biopsies in paediatric patients. The use of smaller (18 or 20-gauge) cutting needles would reduce the complications rate while allowing retrieval of sufficient tissue for histologic diagnosis.

Bile acids reversible effects on small intestinal permeability. An in vitro study in the rabbit.

To define the action of deconjugated bile acids on the small intestinal permeability in an in vitro system, we investigated the effects of chenodeoxycholic acid and ursodeoxycholic acid on the rate of transmural flux of lactulose in jejunal and ileal mucosa of rabbits, stripped of their muscle layers and mounted in Ussing chambers. In a series of experiments, tissue samples from small intestinal segments either exposed to bile acids or not also were examined by scanning and transmission electron microscopy to study the integrity of the tight junctions. Results show that chenodeoxycholate, starting at the concentration of 0.1 mM, enhanced in a dose-related manner the transepithelial flux of lactulose in the ileum. Both chenodeoxycholate (0.5 mM) and ursodeoxycholate (0.5 mM) significantly increased mucosal permeability to lactulose in jejunum and ileum; the effect of chenodeoxycholate was also shown to be reversible, as it completely disappeared within 40 min after its withdrawal and it did not result in permanent changes of epithelial transport function. Finally, the tight junctions appeared loosened by the addition of 1 mM chenodeoxycholate, suggesting that this is the major site of the transient bile acid increase of small intestinal permeability to compounds such as lactulose, having a molecular radius wider than 0.5 nm.

Increased tight junction width in two children with Ménétrier's disease.

Protein-losing enteropathy (PLE) and edema are usually the most prominent clinical features in children with Ménétrier's disease. However, the changes in gastrointestinal mucosa that can cause PLE have not been described yet in children. We studied by electron microscopy the mucosa of the gastric fundus, which is the site where macroscopic changes are most prominent, in two children with Ménétrier's disease. We found that tight junction width was increased to 10.5 +/- 0.94 nm (mean +/- 1 SD) in one child and to 9.7 +/- 0.7 in the other. Tight junction width returned to normal when PLE and edema subsided. These ultrastructural changes were similar to those described in adults with the disease, although the clinical course of Ménétrier's disease is very different in adults and in children. Both patients showed evidence of cytomegalovirus (CMV) infection, as indicated by increasing IgG antibodies against the virus or recovery of the virus in the urine. Although Helicobacter pylori was found in the antral mucosa of one patient, the clinical course of the disease was not related to this microorganism. We conclude that increased tight junction width plays a role in PLE seen in Ménétrier's disease in children and that CMV, rather than Helicobacter pylori, is associated with the disease.