Pulmonary arterial hypertension is a progressive, symptomatic, and ultimately fatal disorder for which substantial advances in treatment have been made during the past decade. This article reviews the recent advances in the field of pulmonary arterial hypertension (PAH). Epidemiology, genetics, treatment and prognosis will be the main focus of this update.

Background: Repeated arousals during sleep have been known to be associated with excessive daytime sleepiness and cardiovascular complications. We investigated the relationship between arousal indices and clinical parameters. Methods: We retrospectively reviewed medical records of 41 patients who performed polysomnography for a diagnosis of obstructive sleep apnea syndrome. We defined total arousal index (TAI) as the number of arousals per hour and respiratory arousal index (RAI) as the number of arousals associated with apnea or hypopnea per hour. Results: There were significant positive correlations between arousal indices and apnea-hypopnea index (AHI) (RAI vs. AHI, r=0.958, p<0.001; TAI vs. AHI, r=0.840, p<0.001). RAI and mean oxygen saturation showed a significant negative correlation with each other (r=-0.460, p=0.002). TAI revealed a significant positive correlation with mean systolic blood pressure (MSBP) and mean diastolic blood pressure (MDBP) (TAI vs. MSBP, r=0.389, p=0.014; TAI vs. MDBP, r=0.373, p=0.019). There was no significant correlation between arousal indices and parameters of sleepiness. RAI had a significant positive correlation with body mass index (BMI) and neck circumference (NC) (RAI vs. BMI, r=0.371, p=0.017; RAI vs. NC, r=0.444, p=0.004). When partial correlation analysis was performed to adjust for other variables, there was significant correlation between RAI and AHI (r=0.935, p<0.001). Conclusion: This study shows that respiratory arousal index could be a useful index reflecting of severity of obstructive sleep apnea syndrome. Arousal during sleep would be concerned in the development of cardiovascular complication of obstructive sleep apnea. And some anthropometric factors would contribute to the development of arousals during sleep. Further studies are needed to clarify any cause-effect relationship.

Background: Pemetrexed, a multi-targeted antifolate has been used as a second line treatment against non-small cell lung cancer (NSCLC). We aimed to clarify the efficacy and survival according to line of treatment, histologic type, and expression of thymidylate synthase (TS). Methods: Ninety-eight patients were treated with pemetrexed as a second line treatment (n=43) or as an additional course of treatment (n=55). TS expression was studied with immunohistochemistry and graded as 0 to 3 based on the extent of expression. Results: The response rate (RR) in 98 subjects was 10.2% and the disease control rate (DCR=PR+SD) was 30.6%. RR and DCR were 12.7% and 32.7% in non-squamous cell carcinoma (NSQC) compared to 7.0% and 27.9% in squamous cell carcinoma (SQC) (p>.05). No significant differences in RR and DCR were observed between a second line group (4.7%, 20.9%) and a further line group (14.5%, 38.2%). A similar trend was observed in the 88 response evaluable subjects. TS was expressed in 28.6% (grade 1), 24.5% (grade 2) and 7.1% (grade 3), respectively, and it was not expressed in 39.8% of subjects. TS expression rate was significantly higher in the SQC (72.1%) compared to NSQC (50.9%, p=0.033). However, the efficacy of pemetrexed was not significantly different by the extent of TS expression. Conclusion: Pemetrexed showed efficacy, not only in a second-line setting, but also in further lines of treatment for NSCLC. The efficacy of pemetrexed tended to be higher in patients with NSQC compared to SQC. TS expression rate was significantly higher in SQC compared to NSQC.

Background: To examine the recovery rate of nontuberculous mycobacteria (NTM) from respiratory specimens and the clinical course of NTM pulmonary disease at a 700-bed secondary hospital. Methods: This study analyzed the results of 843 acid-fast bacilli (AFB) culture-positive respiratory specimens from 650 subjects collected between May 2003 and April 2008. In addition, the clinical course of NTM pulmonary disease, diagnosed using criteria established by the American Thoracic Society, was examined. Results: There were 67 (7.9%) NTM isolates recovered from 52 (8.0%) subjects. Among the 535 AFB smear-positive specimens, 34 (6.3%) NTM isolates were recovered. There were 33 (10.7%) NTM isolates were recovered from 308 AFB smear-negative specimens. Of 52 subjects with isolated NTM, M. intracellulare was the most common species at 73.1% (n=33), followed by M. kansassi (n=7), M. abscessus (n=2), M. fortuitum (n=2), and M. avium (n=1). Sixteen (30.8%) patients had NTM pulmonary disease and the most common causative organism was M. intracellulare (n=14, 87.5%). Of these, 6 cases attained negative conversion in culture, 4 cases failed to attain negative conversion because of poor cooperation or expiration from complicated underlying lung disease, and 5 cases were transferred to a higher-grade hospital. Conclusion: The recovery rate of NTM from respiratory specimens was relatively low and the most common species was M. intracellulare. Patients with NTM pulmonary disease showed variable clinical outcomes.

Background: Serum procalcitonin level has been considered prognostic during sepsis and septic shock. We investigated the significance of procalcitonin in critically ill patients with respiratory infections. Methods: The patients who had radiographically diagnosed diffuse lung infiltrations were enrolled on a prospective basis. Bronchoalveolar lavage (BAL) fluid for the purpose of quantitative cultures (≥10(4) cfu/mL) was obtained from all patients. Serum procalcitonin levels determined by PCT-Q kit were measured on BAL day and classified as follows; <0.5 ng/mL, 0.5∼2.0 ng/mL, 2.0∼10.0 ng/mL and >10.0 ng/mL. We analyzed the patient`s characteristics according to outcome; favorable or unfavorable, defined as death. Results: Patients from the following categories were included: medical 17 (47.2%), surgical 9 (25%), and burned 10 (27.8%). APACHE II scores on admission to intensive care unit were 11.5±6.89 and 11 (30.6%) had unfavorable outcomes. A procalcitonin level ≥0.5 ng/mL was in 17 (47.2%) of all. On univariate analysis, the frequencies of burn injury, mechanical ventilation, multiple organ failure, and a procalcitonin level ≥0.5 ng/mL were more often increased in patients with unfavorable outcomes than in those with favorable outcomes (p<.05). Also, a higher procalcitonin range and ventilator-associated pneumonia (VAP) were more closely associated with an unfavorable outcome (p<.05). However in multivariate analysis, a strong predictor of unfavorable outcome was burn injury (p<.05). A procalcitonin level ≥0.5 ng/mL was more sensitive in predicting VAP than unfavorable outcome. Conclusion: A higher procalcitonin level seems to be associated with VAP, but further study is required to know that procalcitonin would be a prognostic marker in critically ill patients with respiratory infections.

Background: Ventilator-associated pneumonia caused by multi-drug resistant Acinetobacter baumannii has been increasing and growing as a threat in intensive care units. Limited therapeutic options have forced clinicians to choose colistin with or without combination of other antibiotics. We tried to compare the effectiveness between colistin monotherapy and combination therapy based on in vitro synergistic tests. Methods: From January 2006 to December 2007 in medical ICU of a tertiary care hospital in Korea, We reviewed the medical records of patients treated with intravenous colistin due to ventilator-associated pneumonia caused by multi-drug resistant Acinetobacter baumannii. Results: A total of 41 patients were analyzed. 22 patients had been treated with colistin monotherapy and 19 patients with colistin and combination antibiotics that were found to have in vitro synergistic effects. Baseline characteristics were similar in both groups but the mean duration of colistin administration was significantly longer in the combination group (19.1±11.2 days vs. 12.3±6.8 days, p=0.042). There were no significant differences in outcome variables between the two groups. Conclusion: Combination treatment based on the in vitro antimicrobial synergy test did not show better outcomes compared with colistin monotherapy in VAP caused by multi-drug resistant A. baumannii.

Background: Pain is one of the most troublesome problems caused by malignancy. We evaluated the change in pain status according to observance of NCCN guidelines in lung cancer patients. Methods: Lung cancer patients complaining of pain at admission were examined. The pain was assessed with visual analogue scale (VAS) for 20 days and moderate-to-severe pain was defined as more than VAS level 3. The guideline observance was classified as high (more than 80%), medium (50∼79%) and low (less than 50%). Results: Among the total 91 lung cancer patients with pain, 34 patients (37%) had moderate-to-severe pain. Their average VAS score at admission was 5.6. It decreased to 2.9 after a 20-day period of pain management. The time to reach a VAS less than 3 was 3 days in a high guideline observance group, while it took 6 days in a low observance group. In addition, the pain in the high observance group was controlled to less than 3 VAS level in 86% of patients, whereas only 25% of patients in the low observance group succeeded. Conclusion: Pain was more effectively controlled when the dose of drugs was modified according to NCCN guidelines in lung cancer patients indicating the importance of guideline observance in pain management.

Henoch-Schonlein purpura (HSP) is an immunologically mediated systemic vasculitis of small blood vessels that primarily involves the skin, gastrointestinal tract, joints and kidneys. HSP is a common vasculitic syndrome in children who, in most cases, achieve complete recovery. Pulmonary hemorrhage is a very rare manifestation of HSP. The authors present a case of a 46-year-old male presenting with pulmonary hemorrhage and renal involvement and the diagnosis of HSP. The patient responded to prednisolone therapy.

Sparganosis is a zoonosis caused by the migrating larvae of cestode genus Spirometra. We report a rare form of sparganosis that invades the lung. A 44-year-old man presented with newly appeared pulmonary nodules that were found accidentally on regular medical checkup, and on sequential chest CT, which we checked at an interval of every 2 months, revealed that the pulmonary lesion had migrated. The patient had a medical history of having undergone surgical excisions for sparganosis in muscles and in subcutaneous tissues of the lower abdomen, perianus, thigh, right axilla, and scapula area, several times over 7 years. A right middle lobectomy was performed and the lesion was diagnosed as sparganosis based on the characteristic histological findings.

Henoch-Schonlein Purpura (HSP) is a systemic vasculitis involving small vessels with the deposition of immune complexes containing IgA and C3, which is characterized by associated skin, joint, renal, and gastrointestinal manifestations. Although there were several causes such as autoimmunity, infection, and drugs, it also can be presented as a form of vasculitidies associated with malignancies. We report a case of HSP developed during treatment for non-small cell lung cancer in a 66-year-old man. Multiple purpuric skin lesions occurred in both legs after the first cycle of chemotherapy, which was diagnosed as HSP by clinical and pathologic examinations. Due to the itching sensation, topical steroid was applied and the patient was improved 3 weeks later without a scheduled change in chemotherapy.