Hadil A. Al-Otair

Prediction of Pulmonary Hypertension in Patients with or without Interstitial Lung Disease: Reliability of CT Findings

PURPOSE To study the reliability of pulmonary vascular measurements based on computed tomography (CT) in the prediction of pulmonary hypertension (PH) in patients with advanced interstitial lung disease (ILD) compared with those without ILD. MATERIALS AND METHODS The study was approved by the Institutional Review Board. All patients gave written informed consent. A prospective study of 134 patients who underwent right-sided heart catheterization and chest CT scanning within 72 hours of admission was conducted. Patients were divided into two groups-one with ILD (group A, n = 100) and one without ILD (group B, n = 34). CT measurements of the main pulmonary artery diameter (PAD), the ratio of PAD to the ascending aorta diameter (AAD), right pulmonary artery diameter (RPAD), and left pulmonary artery diameter (LPAD) were obtained. Univariate logistic regression analysis was performed, and receiver operating characteristic curves were constructed to assess the predictive ability of vascular measurements obtained by using CT in the identification of PH. RESULTS Main PAD was significantly greater in patients with PH than in those without PH in both groups (group A, P = .008; group B, P = .02). A PAD greater than 25 mm in patients with ILD was predictive of PH, with a sensitivity of 86.4% (32 of 37), a specificity of 41.2% (26 of 63), a positive predictive value of 46.3% (32 of 69), and a negative predictive value of 83.8% (26 of 31). In patients without ILD, a PAD greater than 31.6 mm and an LPAD greater than 21.4 mm were predictive of PH (sensitivity, 47.3% [nine of 19]; specificity, 93.3% [14 of 15]; positive predictive value, 90.0% [nine of 10]; and negative predictive value, 58.3% [14 of 24]). CONCLUSION CT-derived vascular measurements were of limited utility in the prediction of PH in patients with ILD compared with those without ILD.

Unusual cause of respiratory distress misdiagnosed as refractory asthma

We report a young lady, who was labeled as a case of refractory asthma for a few years, based on history of shortness of breath on minimal exertion, noisy breathing and normal chest radiograph. Repeated upper airway exam by an otolaryngologist and computerized tomography scan, were normal. On presentation to our hospital, she was diagnosed to have fixed upper airway obstruction, based on classical flow-volume loop findings. Fibroptic bronchoscopy revealed a web-shaped subglottic stenosis. The histopathology of a biopsy taken from that area, showed non-specific inflammation. No cause for this stenosis could be identified. The patient was managed with rigid bronchoscopy dilatation, without recurrence. We report this case as idiopathic subglottic stenosis, that was misdiagnosed as refractory bronchial asthma, stressing the importance of performing spirometry in the clinic. ubglottic stenosis is a serious and sometimes S life- threatening condition. It results from narrowing of the subglottic airway, which is housed in the cricoid cartilage. It is the narrowest area of the airway, since it is a complete, non expandable and a non pliable ring. Stenosis in this area can be congenital, which is usually diagnosed during childhood, or acquired. Typically, acquired subglottic stenosis has an insidious onset, where early manifestations are usually mistaken for other respiratory disorders, like bronchial asthma and bronchitis. We report a patient with acquired subglottic stenosis of unknown etiology. She was misdiagnosed as a case of refractory bronchial asthma for few years, until her condition was finally diagnosed with the help of spirometry and fibroptic bronchoscopy. Successful dilatation was performed with rigid bronchoscope, without recurrence. Case Report

Unusual case of central alveolar hypoventilation

Central alveolar hypoventilation is rarely encountered. This case report describes a young woman who was recently diagnosed with hypertension and ischemic heart disease. She presented to the emergency room with hypercapnic respiratory failure, for which she was mechanically ventilated. This was preceded by an acute upper respiratory tract infection. She was initially suspected to have Guillain-Barré syndrome, but further investigations ruled out neuromuscular or autoimmune disorders. Sleep-related hypoventilation was suspected after she experienced recurrent apneas at night that resulted in re-intubation. Polysomnographic studies confirmed episodes of central apnea and hypopnea during sleep, with significant carbon dioxide retention and oxygen desaturations. She required nocturnal ventilation via a tracheostomy tube until a diaphragmatic pacer could be placed. Using bi-level positive airway pressure and average volume-assured pressure support together with the diaphragmatic pacer, adequate ventilation during sleep was achieved.

Assessment of antigen presenting cell infiltration in lung tissues of patients with bronchiectasis

Background: Bronchiectasis is a chronic disease characterized by permanent dilatation of the conducting airways accompanied by sustained inflammation. Aims: To assess whether chronic inflammation of lungs in bronchiectasis is associated with alterations in the numbers of infiltrating antigen presenting cell (APC). Setting and Design: Lobectomy specimens from 12 nonsmoker, nonasthmatic patients with acquired (noncongenital) bronchiectasis and six control patients were included in the study. Histopathology slides were reviewed, and immunohistochemical markers for dendritic cells (DCs) macrophages and Langerhans cells have been applied and analyzed. Materials and Methods: Tissue specimens were stained by immunohistochemistry using markers for DCs (CD83 and CD23), macrophages (CD68 and CD163), and Langerhans cells (CD1A and S-100 protein). The mean cell counts of stained cells in five high power microscopic fields were recorded. Statistical Analysis Used: Descriptive statistics, mean, standard deviation, median, and interquartile range were used. A nonparametric Mann-Whitney U-test was used to compare cell counts between bronchiectasis and control patients. P <0.05 was considered significant. Results: The mean age of patients with bronchiectasis and controls was 36.7 ± 16.6 and 31.8 ± 22.6 years, respectively. The predominant cell type among the patients was macrophage (median 50.5) followed by DCs (median 44.85), histiocytes (median 32), and Langerhans cells (median 5%). Compared to the controls a significantly higher number of macrophages (P = 0.01), DCs (P = 0.001), and Langerhans cells (P = 0.014) were present. Conclusion: Chronic inflammatory response in acquired (noncongenital) bronchiectasis is most probably mediated by increased infiltration of APCs in lung tissues.