Nasal Brush Biopsy Research Articles

Primäre Ziliendyskinesie als Ursache neonataler Atemnot

Primary ciliary dyskinesia (PCD) is a hereditary disorder of structure and function of the cilia of respiratory epithelium of the upper and lower airways. Prevalence is estimated with 1:15 000 to 1:30 000 births. We present a newborn infant with respiratory distress caused by PCD. On the first day of life, the male newborn developed dyspnoe and cyanosis, so that CPAP and short term ventilation was necessary. Varying atelectasis impressed on the chest radiographs and the diagnosis of PCD was made by nasal brush biopsies. Causative is a lack of the inner dynein arms of the cilia. The clinical features of newborns with the diagnoses of PCD are listed and compared with the own case. PCD is a rare cause of neonatal respiratory distress and should be considered in term infants with unknown and prolonged course even if Situs inversus is lacking.

Disrupted ciliated epithelium shows slower ciliary beat frequency and increased dyskinesia

Ciliary function studies for the diagnosis of primary ciliary dyskinesia (PCD) are usually performed on nasal brush biopsy samples. It is not uncommon to find disrupted epithelial strips of tissue in these samples, and occasionally throughout a sample. The aim of the present study was to determine if cilia on disrupted ciliated epithelial edges beat with a normal pattern and frequency similar to that of cilia on undisrupted edges. Nasal brush biopsy samples from 42 children in whom the diagnosis of PCD was excluded were assessed. The epithelial strips were categorised into five groups: intact undisrupted ciliated epithelial edge, ciliated epithelial edge with minor projections, ciliated epithelial edge with major projections, an isolated ciliated cell on an epithelial edge and single unattached ciliated cells. Ciliary beat frequency and beat pattern of 50 samples from each group were determined using high speed digital video microscopy. The cilia on epithelial edges with varying degrees of disruption showed significantly reduced beat frequency and significantly increased dyskinesia compared with those on intact, undisrupted ciliated epithelial edges. Ideally, the assessment of ciliary beat pattern and frequency for PCD diagnosis should only be performed on undisrupted ciliated edges.

Oralfacialdigital‐like syndrome with respiratory tract symptoms from birth and ultrastructural centriole/basal body disarray

A girl with polydactyly has had respiratory tract problems, including atelectasis, since birth. She has a high arched palate, a tongue hamartoma and dysmorphic face. Electron microscopy of nasal and bronchial brush biopsies repeatedly revealed centriole/basal body disarray and extreme sparseness of cilia. At the age of 2 years and 11 months, she displayed retardation of both motor and mental skills. The manifestations tally with a ciliopathy, partly with the Bardet--Biedl syndrome (BBS) but especially with the oralfacialdigital syndrome (OFDS); however, with the addition of persistent respiratory tract problems. As these two syndromes are considered to be due to mutations affecting the centriole/basal body apparatus, the ultrastructural demonstration of disarray of these structures, never before demonstrated in such a patient, is of fundamental interest.

A Comparison of Experimental Methods in Molecular Chronic Rhinosinusitis Research

Research into the molecular pathogenesis of chronic rhinosinusitis (CRS) requires the collection and analysis of sinonasal tissue. Recent gene expression studies have used either surgical tissue specimens or isolated epithelial cell preparations. Here, we compare cultures of nasal epithelial cells, nasal brush biopsy, and whole ethmoid mucosa with respect to expression of innate immune genes. Ethmoid mucosa was collected intraoperatively from 12 CRS and control patients. This tissue either was processed whole for mRNA extraction or was used to generate primary nasal epithelial cell cultures. After 6 weeks, epithelial cells in culture were assessed for multiple innate immune proteins by flow cytometry. In parallel, middle meatal brush biopsy specimens were obtained from the same patients and studied acutely in a similar fashion by flow cytometry. Expression of innate immune genes was determined in whole tissue samples by real-time polymerase chain reaction. Flow cytometry revealed that brush biopsy specimens contain 75% epithelial cells, whereas primary nasal epithelial cell cultures were pure. Epithelial cells derived from individual subjects expressed very similar levels of innate immune markers whether studied acutely or after 6 weeks in culture. Whole tissue mRNA levels were variable and not correlated to epithelial expression. The choice of experimental methodology can greatly influence the results and interpretation of CRS research. Primary nasal epithelial cells maintain their innate immune receptor expression profile when grown in prolonged culture in vitro. These findings imply that alterations in innate immune gene expression in CRS may be intrinsic to the epithelial cells, even outside of their in vivo microenvironment.

Formaldehyde-induced DNA adducts as biomarkers of in vitro human nasal epithelial cell exposure to formaldehyde

Formaldehyde (FA) is a mutagen that, at high concentrations and long durations, has been reported to cause nasal cancer in rats and in some humans. The level of FA-induced modified DNA in nasal cells should serve as a biomarker of FA exposure and effect. In the present study, a high-performance liquid chromatography (HPLC)-ultraviolet (UV) method at 254 nm was developed and optimized to detect and quantify hydroxymethyldeoxynucleosides after the isolated DNA in exposed human nasal epithelial cells (HNEC) was enzymically digested. Normal and modified deoxynucleosides were successfully resolved from one another and from tissue and enzyme blank interferences. The viability of HNEC exposed to FA in solution for 24 h decreased, and there was a linear dose response between % nonviability and FA dose from 10 to 500 microg/mL. Amounts of 18.0 +/- 1.5 pmol N6-dA and 12.0 +/- 1.2 pmol N2-dG derivatives were determined in a 10 microL injection after 1.4 x 10(7) HNEC (106 microg DNA) were exposed to 500 microg/mL in solution. The respective tissue concentrations in pmol hydroxymethyldeoxynucleoside/mg DNA were 170 +/- 14 and 113 +/- 11. The lower quantifiable limits were about 97 and 88 pmol/mg DNA, respectively. Diffusive exposure of HNEC to air FA up to 100 ppm (v/v) for 24 h did not produce quantifiable hydroxymethylnucleosides. FA-modified deoxynucleosides may be useful biomarkers for FA exposure in biological monitoring samples taken by nasal lavage or brush biopsy.

A case of Wiskott‐Aldrich syndrome with cilial immotility

We report the case history of a 25-year-old man who was diagnosed as having Wiskott-Aldrich syndrome in infancy. He had the typical features of severe eczema, thrombocytopenia and recurrent sinopulmonary infection. By his late teenage years he had developed bronchiectasis despite having normal levels of immunoglobulin and IgG subclasses. His functional antibody responses to tetanus toxoid and pneumococcal vaccine were suboptimal (15% and 52% of normal respectively). Regular intravenous immunoglobulin therapy resulted in a reduced frequency and severity of infection but despite this treatment he continued to get respiratory infections. In April 1999 he presented with three episodes of acute gastrointestinal haemorrhage. CT scan of the abdomen and arteriography showed multiple arterial aneurysms with evidence of active haemorrhage within the liver and upper small bowel. Inflammatory markers (ESR and C-reactive protein) were markedly elevated and he was diagnosed as having acute inflammatory vasculitis as a complication of his primary immune disorder.1 Prednisone and cyclophosphamide therapy were deemed necessary to treat the vasculitis and prevent further life-threatening haemorrhage. Before immunosuppressive therapy was started, seminal fluid samples were obtained for storage. Analysis revealed not only a low sperm count (<2 × 106/ml) but also the fact that all spermatozoa were immotile. In order to investigate cilial function more fully, nasal brush biopsy samples were obtained and cilial activity was assessed by a standard method on fresh samples. No evidence of cilial movement was observed in any of the tissue samples. The role of Wiskott-Aldrich Syndrome Protein (WASP) in transmitting signals from CDC42HS to the actin cytoskeleton of cells To our knowledge, this is the first report of cilial immotility as a feature of this condition. Wiskott-Aldrich syndrome is an X-linked primary immunodeficiency disorder characterised by thrombocytopenia, eczema and recurrent infection.2 The gene defect has been identified at the Xp11.22 position on the short arm of the X chromosome and designated the WAS gene.3 A variety of mutations have been described, all of which result in the absence of WAS protein or the production of a functionally defective protein. In normal individuals WAS protein plays a central role in the control of cellular morphology and the organisation of the cytoskeleton of cells.4 Defects in some of these, including actin polymerisation (Figure 1), have been identified and help to explain many of the clinical manifestations of WAS.5 In the past, the increased frequency of infection in this disorder was attributed to impaired antibody production. Some patients, however, including this case, develop sinopulmonary infection and bronchiectasis at an early age which cannot be explained by a defect in antibody production alone and may represent some other defect in the antibacterial defence system of the respiratory tract. It is not clear whether or not cilial immotility occurs in all WAS patients or only in certain genetic variants of the disorder.

Dynamics of nasal eosinophils in response to a nonnatural allergen challenge in patients with allergic rhinitis and control subjects: A biopsy and brush study

Eosinophils are thought to play an important role in the symptomatology and pathophysiology of allergic rhinitis. Most quantitative studies on eosinophils in nasal mucosa have focused on the dynamics of eosinophils in the acute and late phases of the allergic reaction by using different cell sampling techniques. Little is known about the dynamics of eosinophils during a more prolonged period of allergen exposure and the activation of eosinophils induced by allergen challenge. The aim of this study was to investigate the dynamics and activation of the eosinophils in the nasal mucosa of patients with an isolated grass pollen allergy during an out-of-season 2-week allergen exposure, mimicking the natural grass pollen season. Seventeen patients with isolated grass pollen allergy and four control subjects were challenged daily with the allergen during a 2-week period in the winter. Nasal brush specimens were obtained before provocation and each day during the provocation period. Biopsy specimens were obtained once before, six times during, and once after the provocation period. Preparations made of nasal brush and nasal biopsy specimens were stained with the monoclonal antibody BMK 13 and Giemsa stain as paneosinophil markers and with the monoclonal antibody EG2 to identify activated eosinophils. We found significant increases in the total number of eosinophils and the number of activated eosinophils in the epithelium and lamina propria. These increases were most explicit in the second week. BMK 13 was found to be a paneosinophil marker superior to Giemsa staining. Eosinophils are not only involved in the acute and late phases of the allergic reaction but are probably even more involved in the chronic phase.

NONRESOLVING AND RECURRENT PNEUMONIA

The evaluation of recurrent pneumonia involves the consideration of demographic, clinical, and radiologic features and is often quite similar to that undertaken for slowly resolving pneumonia. If the infection is recurrent in a single lobe, intraluminal or extraluminal, obstruction must be suspected. Foreign body aspiration remains the most common remedial cause of pneumonia. Computed tomography and bronchoscopy are useful in the preliminary evaluation of localized obstruction to bronchial drainage and in diffuse abnormalities like bronchiectasis and tracheobronchiomegaly. A recent study suggested that perfusion lung scanning is a good screening test for localized structural disease in children with recurrent pneumonia. Abnormal or diffusely nonhomogeneous patterns (23 patients) were associated with an excellent prognosis. In those 9 patients with lobar or multisegmental perfusion defects, bronchiectasis was found in 5, bronchomalacia in 2, and agenesia and sequestration in 1 each. If pneumonia recurs in the lower lobes, especially in the posterior segments, bronchopulmonary sequestration should be considered. Evaluation should include an aortogram to look for the feeding blood supply from the abdominal or thoracic aorta. This study is not only diagnostic, but provides information required for surgical resection. If the recurrent pneumonia involves multiple lobes, aspiration must be considered first. In this case, an esophogram or endoscopy should provide information about either functional or anatomic obstruction to the esophagus. Patients who present with recurrent diffuse pulmonary infiltrates and wheezing should be evaluated for ABPA and chronic eosinophilic pneumonia as well as asthma. In the pediatric age group, immunoglobulin deficiency, although rare, must be evaluated. Immunoglobulins, using age appropriate norms, should be measured. Sweat chloride determination provides information about the likelihood of cystic fibrosis. In the presence of sinus disease, a nasal brush biopsy or scraping can be performed to assess the ultrastructural abnormalities of dyenin, the microtubules, or radial spokes of cilia. Finally, AIDS should be considered in all patients who have recurrent pneumonias, even when standard risk factors are not elicited in the history.