The emerging ST8 methicillin-resistant Staphylococcus aureus clone in the community in Japan: associated infections, genetic diversity, and comparative genomics.

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) has become a major concern worldwide. In the United States, ST8 CA-MRSA with SCCmecIVa (USA300) has been predominant, affecting the entire United States. In this study, we investigated Japanese ST8 CA-MRSA with new SCCmecIV1 (designated ST8 CA-MRSA/J), which has emerged in Japan since 2003. Regarding community spread and infections, ST8 CA-MRSA/J spread in 16.2-34.4% as a major genotype in the community in Japan, and was associated with skin and soft tissue infections (SSTIs), colitis, and invasive infections (sepsis, epidural abscesses, and necrotizing pneumonia), including influenza prodrome cases and athlete infections, similar to USA300. It spread to even public transport and Hong Kong through a Japanese family. Regarding genetic diversity, ST8 CA-MRSA/J included ST and spa variants and was classified into at least three pulsed-field gel electrophoresis types, ST8 Jα to γ. Of those, ST8 Jß was associated with severe invasive infections. As for genomics, ST8 CA-MRSA/J showed high similarities to USA300, but with marked diversity in accessory genes; e.g., ST8 CA-MRSA/J possessed enhanced cytolytic peptide genes of CA-MRSA, but lacked the Panton-Valentine leukocidin phage and arginine catabolic mobile element, unlike USA300. The unique features of ST8 CA-MRSA/J included a novel mosaic SaPI (designated SaPIj50) carrying the toxic shock syndrome toxin-1 gene with high expression; the evolution included salvage (through recombination) of hospital-acquired MRSA virulence. The data suggest that ST8 CA-MRSA/J has become a successful native clone in Japan, in association with not only SSTIs but also severe invasive infections (posing a threat), requiring attention.

Diagnosis and treatment of patients with spontaneous pneumomediastinum.

BACKGROUND: Although many patients complaining of chest pain visit the emergency department, very few are diagnosed with spontaneous pneumomediastinum (SPM). We present the management of 20 patients with SPM. METHODS: We retrospectively analyzed the clinical features, past history, chest X-rays (CXRs), 64-slice helical computed tomography (CT) images, and clinical course of 20 patients with SPM (19 men and 1 woman) who visited the emergency department of the Tokyo Metropolitan Bokutoh Hospital between 2005 and 2010. RESULTS: SPM predominantly resulted from physical exertion during such activities as sports and weight lifting (8 patients). The most common complaint was chest pain (15 patients), followed by dysphagia (10 patients), and dyspnea (8 patients). Subcutaneous emphysema was detected in 9 patients. The mean body mass index of the patients was 20.8±1.4kg/m(2). Although CXR findings of pneumomediastinum were absent in 5 patients, CT showed findings of the Macklin effect in all patients-interstitial gas was observed in the perihilar area in all patients and in the peripheral lung area in 9 patients (45%). Ten patients were hospitalized. The others received ambulatory care in the form of analgesics without antibiotics. All patients fully recovered without complications. CONCLUSIONS: Our results showed that 64-slice helical CT is more reliable than CXRs for diagnosing SPM. Moreover, some patients with SPM can be treated without hospitalization, thus decreasing medical expenses for these patients.

Evolution and virulence of Panton-Valentine leukocidin-positive ST30 methicillin-resistant Staphylococcus aureus in the past 30 years in Japan.

Methicillin-resistant Staphylococcus aureus (MRSA) includes hospital-acquired MRSA (HAMRSA) and community-acquired MRSA (CA-MRSA). Panton-Valentine leukocidin (PVL)-positive multilocus sequence type 30 (ST30) MRSA is one of worldwide CA-MRSA, which has also persisted in Japan since the 1980s. However, unexpectedly, it was not the same ST30 clone throughout. Before 2000, it was HA-MRSA with spa43 and ψSa3sea (phage Sa3 carrying the sea gene) and only one PVL-positive MRSA in Japan; in the 1980s, ST30 MRSA accounted for 23.5% of HA-MRSA, showed multidrug resistance, had high MICs for oxacillin and imipenem, and caused decubitus and pneumonia in hospitalized patients. A dynamic clonal change (spa43/ψSa3sea→ spa19) occurred around 2000-2002. A rare spa43/ψSa3sea/SCCmecI-IE25923 genotype also emerged. After 2002, the prevalent spa19 clone was CA-MRSA; it accounted for only 0.3% (or less) of MRSA in hospitals but 7.6% of CA-MRSA. Since 2007, PVL-positive CA-MRSA with other ST types (such as ST8, ST22, and ST59) also emerged in Japan, albeit at a low frequency. ST30/spa19 CA-MRSA occasionally caused severe invasive infections and a novel ST1335/spa19 genotype emerged. These ST30/spa19 CA-MRSA and variants were identified by pulsed field gel electrophoresis. Further analysis revealed that PVL-positive ST30/spa19 CA-MRSA is a highlyvirulent, successful clone, having a potential of clonal expansion.

The emerging ST8 methicillin-resistant Staphylococcus aureus clone in the community in Japan: associated infections, genetic diversity, and comparative genomics.

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) has become a major concern worldwide. In the United States, ST8 CA-MRSA with SCCmecIVa (USA300) has been predominant, affecting the entire United States. In this study, we investigated Japanese ST8 CA-MRSA with new SCCmecIVl (designated ST8 CA-MRSA/J), which has emerged in Japan since 2003. Regarding community spread and infections, ST8 CA-MRSA/J spread in 16.2-34.4% as a major genotype in the community in Japan, and was associated with skin and soft tissue infections (SSTIs), colitis, and invasive infections (sepsis, epidural abscesses, and necrotizing pneumonia), including influenza prodrome cases and athlete infections, similar to USA300. It spread to even public transport and Hong Kong through a Japanese family. Regarding genetic diversity, ST8 CA-MRSA/J included ST and spa variants and was classified into at least three pulsed-field gel electrophoresis types, ST8 Jα to γ. Of those, ST8 Jß was associated with severe invasive infections. As for genomics, ST8 CA-MRSA/J showed high similarities to USA300, but with marked diversity in accessory genes; e.g., ST8 CA-MRSA/J possessed enhanced cytolytic peptide genes of CA-MRSA, but lacked the Panton-Valentine leukocidin phage and arginine catabolic mobile element, unlike USA300. The unique features of ST8 CA-MRSA/J included a novel mosaic SaPI (designated SaPIj50) carrying the toxic shock syndrome toxin-1 gene with high expression; the evolution included salvage (through recombination) of hospital-acquired MRSA virulence. The data suggest that ST8 CA-MRSA/J has become a successful native clone in Japan, in association with not only SSTIs but also severe invasive infections (posing a threat), requiring attention.

Clinical characteristics of healthcare-associated pneumonia in a public hospital in a metropolitan area of Japan.

Healthcare-associated pneumonia (HCAP) is a new category that is essential in the present aging society. Knowing the different characteristics and outcomes between patients with HCAP and community-acquired pneumonia (CAP) would help physicians manage and treat HCAP patients. Although HCAP is thought to be heterogeneous in regions, there are no reports from a metropolitan area in Japan. We retrospectively reviewed the clinical findings of all consecutive pneumonia patients who required hospitalized care in our hospital between April 2006 and March 2010. There were 184 (35.0%) patients with HCAP and 342 (65.0%) patients with CAP. Previous hospitalization within 90 days of the infection was the most common criterion for HCAP (63.0%). HCAP patients were significantly older than CAP patients (82.5 vs. 70.0 years, P < 0.001). The percentage of patients with poor functional status was higher in HCAP than CAP (64.0% vs. 26.6%, P < 0.001). Hospital mortality was significantly higher in HCAP patients than in CAP patients (15.8% vs. 5.0%, P < 0.001). Low levels of serum albumin (odds ratio, 0.126; 95% CI, 0.025-0.640; P = 0.012) and high scores in the ADROP (age, dehydration, respiratory failure, orientation, and blood pressure) system (odds ratio, 2.846; 95% CI, 1.449-5.587; P = 0.002) were the risk factors for HCAP mortality. In conclusion, patients with HCAP have different epidemiological characteristics compared with those with CAP in a metropolitan area of Japan. Outcomes and risk factors for mortality of patients with HCAP included poor nutritional status and high severity scores on the pneumonia severity scoring system.

[CPT-11 chemotherapy for a hemodialysis patient with small-cell lung cancer].

We report a hemodialysis patient with extensive small-cell lung cancer who was administered CPT-11(50mg/m2)chemotherapy and achieved a partial response after four courses of chemotherapy. Hemodialysis was performed 24 hours after the first course of CPT-11 was completed. Because the patient developed thrombocytopenia and pneumonia, hemodialysis was performed 4 hours following the second course of chemotherapy, after which grade III bone marrow suppression was observed. The plasma concentrations of CPT-11 and its metabolic products(SN-38 and SN-38G)were measured during both courses. A pharmacokinetic study showed that the plasma concentration of CPT-11 after the first course was relatively high, and that the kinetics was similar to that in a non-dialysis case. However, 4 hours after hemodialysis, the concentrations of CPT-11 and SN-38G were re-elevated, and showed a sustained level higher than that obtained 24 hours after hemodialysis. Further study is needed to determine the optimal dosages of CPT-11, and the best time to conduct hemodialysis for chronic cancer patients requiring it.

[A case of sarcoidosis with an endobronchial polypoid lesion].

A 59-year-old woman complained of impaired vision. She visited an ophthalmologist and glaucoma was diagnosed. In July 200X, she was admitted to our hospital for further examination. Chest radiography and CT showed lymphadenopathy in the mediastinum and bilateral hilum. Bronchofiberscopy revealed mucosal hypervascularity and a polypoid lesion at the orifice of the left B8a. A transbronchial biopsy specimen of the polypoid lesion showed non-caseating epithelioid cell granuloma. On bronchoalveolar lavage, both the proportion of lymphocytes and the CD 4/8 ratio had increased. We diagnosed sarcoidosis with an endobronchial polypoid lesion. The patient has been observed without therapy since, and after a year the polypoid lesion is the same size on 3D CT scans. This is a very rare case of endobronchial sarcoidosis presenting as a polypoid lesion.

Emergence of the community-acquired methicillin-resistant Staphylococcus aureus USA300 clone in Japan.

We isolated methicillin-resistant Staphylococcus aureus (MRSA) from a 3-month-old Indian girl who was born in the United States, moved to Japan, and suffered from subcutaneous abscesses in 2007. The MRSA (strain NN36) belonged to multilocus sequence type (ST) 8, exhibited agr1, staphylococcal cassette chromosome mec (SCCmec) type IVa, and coagulase type III, and was positive for Panton-Valentine leukocidin (PVL) and the arginine catabolic mobile element (ACME), just like the USA300 clone, which is the predominant community-acquired MRSA (CA-MRSA) in the United States. Strain NN36 shared an identical pulsed-field gel electrophoresis (PFGE) pattern with the USA300 clone. Although the USA300 clone is of spa1, strain NN36 possessed spa985. Strain NN36 was resistant to erythromycin and kanamycin, in addition to beta-lactam agents (e.g., oxacillin). The data suggest that the USA300 clone has emerged in Japan. Because the USA300 clone has recently spread to European countries, surveillance of the USA300 clone should be actively performed in Japan.

[Clinical analysis of patients with tuberculosis admitted on an emergency cases].

A retrospective study was made of 75 patients with tuberculosis and tuberculous pleurisy who received medical care in our hospital from 2002 through 2006. Of the 75 patients, 9 were admitted as tertiary emergency cases, and 12 patients were admitted by ambulance as secondary emergency cases. We studied the reason for their emergency medical admission, and the process of diagnosing 21 patients as tuberculosis. In some cases, the reasons for emergency admission were cardiorespiratory arrest, loss of consciousness, and injury resulting from a traffic accident, not common symptoms of tuberculosis such as dyspnea, hemoptysis and bloody sputum. Chest radiographic findings of most patients showed tuberculosis, and other cases were likely to be diagnosed as tuberculosis from their medical history or back-ground such as being homeless, previous tuberculosis, and receiving for therapy of tuberculosis. It was not so difficult to diagnose our cases as tuberculosis, nevertheless we may have an unconscious patient with normal chest radiograph. These data suggest that any patients visiting the emergency room may possibly have tuberculosis even if they are without respiratory symptoms.

[Case of acute respiratory distress syndrome treated with direct hemoperfusion using a polymyxin B immobilized fiber colum].

During a 54-year-old woman's visit to a hot-spring resort, she suffered a fever and became dizzy and unable to speak clearly. She was admitted to our hospital due to serious pneumonia and respiratory failure type I. She was treated with antibiotics, but her condition became worse and developed into acute respiratory distress syndrome (ARDS). She was intubated and received artificial ventilation. Her blood pressure gradually decreased and she suffered septic shock probably due to endotoxin with gram negative coccus infection. Subsequently, she was treated with a direct hemoperfusion using a polymyxin B immobilized fiber column (PMX-DHP), which resulted in an improvement of oxygenation. However, her pneumonia led to the development of septic shock with gram negative coccus infection, and PMX-DHP treatment was resumed. After PMX-DHP re-treatment, she recovered gradually in intensive care including prone positioning ventilation.

Suppressive activity of tiotropium bromide on matrix metalloproteinase production from lung fibroblasts in vitro.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is characterized by airway remodeling with an accumulation of inflammatory cells. There is also increasing evidence that metalloproteinases (MMPs) may contribute to the pathogenesis of COPD, but the influence of agents that used for the treatment of COPD is not well understood. OBJECTIVE: We evaluated whether tiotropium bromide hydrate (TBH), a M3 muscarinic receptor antagonist, could inhibit MMP production from lung fibroblasts (LFs) in response to tumor necrosis factor (TNF)-alpha stimulation. METHODS: LFs were established from normal lung tissues taken from patients with lung tumors. LFs (5 x 10(5) cells/ml) were stimulated with TNF-alpha in the presence of various concentrations of TBH. After 24 h, culture supernatants were obtained and assayed for the levels of MMPs and tissue inhibitor of metalloproteinases (TIMPs) by ELISA. The influence of TBH on mRNA expression of MMPs and TIMPs in 4h-cultured cells was also examined by real-time RT-PCR. Furthermore, nuclear factor-kappaB (NF-kappaB) and activator protein-1 (AP-1) in LFs treated with TBH for 4h was examined by ELISA. RESULTS: TBH at more than 15 pg/ml inhibited the production of MMP-2 from LFs after TNF-alpha stimulation, whereas TIMP-1 and TIMP-2 production was scarcely affected by TBH through the suppression of both mRNA expression and transcription factor, NF-kappaB, activation in LFs induced by TNF-alpha stimulation. CONCLUSION: These results suggest that the attenuating effect of TBH on MMP-2 production from LFs induced by inflammatory stimulation may be additional beneficial therapeutic effects not directly relating to its bronchodilatory effects.

Development of a loop-mediated isothermal amplification method for diagnosing Pneumocystis pneumonia.

Loop-mediated isothermal amplification (LAMP) is a novel, rapid nucleic acid amplification method with high specificity and sensitivity under isothermal conditions. In this study a LAMP assay for diagnosing Pneumocystis pneumonia (PCP) was developed. Oligonucleotide primers specific for Pneumocystis species were designed corresponding to 18S rRNA gene sequences. The assay, performed for 30 min at 61 degrees C, was capable of detecting 50 copies per tube (2 x 10(3) copies ml(-1)) in 30 min and did not show cross-reactivity to other species of fungi, including the genera Candida, Aspergillus and Cryptococcus. A total of 21 of 24 clinical specimens (sputum and bronchoalveolar lavage fluid) from patients with suspected PCP tested positive using the LAMP assay by real-time fluorescence detection. The results of the LAMP reaction were also observed by real-time turbidity detection and end-point visual turbidity or fluorescence detection. With real-time fluorescence detection, melting curves of the products were effective at distinguishing specific amplification from non-specific amplification or self-amplification. Visual detection was also possible as a rapid and easy assay using only a heat block and a black light.

[Risk factors associated with the duration of hospitalization in emergency admitted patients with aspiration pneumonia].

We retrospectively analyzed risk factors which affect the duration of hospitalization of patients who were given diagnoses of aspiration pneumonia and admitted on an emergency basis for 24 hours because of acute events in emergency. The research was conducted on 67 hospitalized patients aged 25-99. who were admitted because of aspiration pneumonia from March 2002 to May 2004. We analyzed the relationships between the duration of hospitalization and factors such as age, sex, severity of pneumonia, number of lobes with inflammation and the duration of tracheal intubation. The mean duration of hospitalization was 24.8 days which was approximately 1.6 times as long as that of all diseases in our hospital. Simple regression analysis suggested that the mean duration of hospitalization correlates significantly with age and the duration of hospitalization, while multiple regression analysis indicates that age is the only significant factor related to duration of hospitalization. However, there was no significant correlation between the duration of hospitalization and the severity of pneumonia. These data indicate that the duration of hospitalization is considerably affected by age, but not the treatment of pneumonia itself. Therefore we should pursue not only the appropriate treatment for aspiration pneumonia but also make an effort for early intervention in the support plan for discharge based on the social background of each elderly patient.

[A case of Mycobacterium abscessus pulmonary infection; effectiveness of clarithromycin, amikacin and imipenem/cilastatin].

A 42-year-old woman presented with persistent cough, bloody sputum and fever. Her chest X-ray film showed an infiltrative shadow with cavitation in the upper lobe of the left lung. Acid-fast-bacilli were shown by sputum smear staining. The anti-tuberculosis drugs isoniazid, refampicin, ethambutol and pyrazinamide were prescribed, but her symptoms and chest X-ray findings did not improve. Findings of MTD and MAC-PCR were negative but Mycobacterium abscessus was confirmed by sputum culture with the DNA hybridization method. Combination therapy with clarithromycin, amikacin and imipenem/cilastatin for one month improved her symptoms and chest X-ray shadow, and clarithromycin monotherapy was carried out for another ten months. Drug susceptibility tests revealed this mycobacterium was sensitive to clarithromycin and amikacin. To determine the environmental factors related to this infection, several samples were examined. Acid-fast-bacilli were present in a smear from the bath room drain. However, to confirm the infectious routes, longer observation is needed. Moreover, serum amyloid protein A and ESR were useful markers to estimate the clinical course.

[Case of primary cavitary sarcoidosis: exacerbation after 16 years from onset].

A 46-year-old man presented with the complaint of cough, fever and dyspnea on exercise. Sixteen years previously stage II sarcoidosis was diagnosed, with an ocular lesion. So far, he had had no respiratory symptoms and was followed up without medication. Two months before his visit, he had a cough. He gradually developed a fever and felt dyspnea on exercise. Chest X-ray showed an infiltrative shadow with a cavity in the right upper lobe. Bronchofiberscopy was performed and the biopsy specimen from the cavity wall revealed noncaseating epitheloid cell granulomas, suggesting primary cavitary sarcoidosis. Corticosterid therapy was started. His symptoms improved rapidly, and the infiltrative shadow on the right upper lobe decreased within one month. The cavity wall was thin on the following computed tomography. Thirty-two cases of primary cavity sarcoidosis were reported in Japan from 1975-2005. The mean age of the patients was 26.5 years old and the ratio of males to females was 13:3. In most cases, corticosteroid therapy was effective and nine spontaneously improved cases were reported. To determine the indications for steroid therapy, further examination is needed.

[A case of successful bronchial artery embolization for primary racemose hemangioma with massive hemoptysis].

We encountered a case of primary racemose hemangioma treatment with successful bronchial artery embolism for massive hemoptysis. A 56-year-old woman with massive hemoptysis was transported to our hospital. The source of the massive hemoptysis was observed to be from around a non-pulsatile polyp covered by normal mucosa occluding the truncus intermedius by fiberoptic bronchoscopy. We stopped the bleeding temporarily using differential lung ventilation, and then bronchial artery angiography was performed. The main right bronchial artery was enlarged, and enlarged and convoluted right peripheral bronchial vessels were also observed. We diagnosed the massive bleeding to be due to racemose hemangioma. A successful bronchial artery embolization (BAE) was performed with gelforms and metallic coils for the treatment of racemose hemangioma. There has been no recurrence of hemoptysis for one year after BAE. There have been many reports on massive hemoptysis as in this patient who were treated by lobectomy, nevertheless we would like to state BAE should be considered as a suitable treatments for primary racemose hemangioma with hemoptysis if there is no recognizable shunt artery.

[Serum amyloid protein A was a useful marker for steroid tapering in a case of MPO-ANCA-associated vasculitis].

A 55-year-old man was admitted complaining of hemosputa, fever and dyspnea. The chest radiographs and computed tomography showed a diffuse alveolar filling pattern; suggesting alveolar hemorrhage. Laboratory data demonstrated renal dysfunction with hematuria and proteinuria and serum MPO-ANCA was also elevated. Respiratory failure progressed rapidly within two days. Steroid pulse therapy and plasmapheresis was performed. Thereafter, symptoms and chest radiograph findings improved dramatically. However proteinuria persisted as steroid administration was tapered. Renal biopsy demonstrated gromeluronephritis and interstitial lymphocyte infiltration. After administering a second course of steroid semi-pulse therapy, her proteinuria improved. C-reactive protein and MPO-ANCA decreased to normal levels after the initial steroid therapy, but serum amyloid A protein (SAA) gradually elevated. The second course of steroid pulse therapy normalized SAA, and proteinuria improved. Based on these findings, SAA seems to be a more sensitive marker for steroid tapering than either CRP or MPO-ANCA.

Nocardia arthritidis sp. nov., a new pathogen isolated from a patient with rheumatoid arthritis in Japan.

Two different bacterial strains with different drug susceptibilities were isolated from the sputum and an inflammatory discharge from a swelling in the left thigh of a patient with rheumatoid arthritis. Both bacterial strains were provisionally assigned to the genus Nocardia on the basis of their morphological and chemotaxonomic characteristics and were further studied in order to establish their taxonomic status. One strain (IFM 10034) was identified as Nocardia farcinica on the basis of its physiological characteristics. The other strain, which was designated Nocardia sp. strain IFM 10035(T), revealed a unique pattern of phenotypic properties that distinguished it from other representatives of established Nocardia species. Comparative 16S rRNA gene sequence studies of Nocardia sp. strain IFM 10035(T) also showed that the bacterium was closely related to the species Nocardia beijingensis. Determination of DNA-DNA relatedness, however, indicated that Nocardia sp. strain IFM 10035(T) could be delineated from N. beijingensis. The genotypic and phenotypic data combined indicated that the bacterium merits description as a new Nocardia species. The name proposed for the new species is Nocardia arthritidis sp. nov., the type strain being IFM 10035(T) (NBRC 100137(T), JCM 12120(T), DSM44731(T)). The present study suggests that Nocardia infections can be caused by multiple species of the bacterium.

[Nationwide surveillance of parenteral antibiotics containing meropenem activities against clinically isolated strains in 2002].

The antibacterial activity of meropenem (MEPM) and other parenteral antibiotics against clinical isolates of 899 strains of Gram-positive bacteria, 1500 strains of Gram-negative bacteria, and 158 strains of anaerobic bacteria obtained from 28 medical institutions during 2002 was measured. The results were as follows; 1. MEPM was more active than other carbapenem antibiotics against Gram-negative bacteria, especially against enterobacteriaceae and Haemophilus influenzae. MIC90 of MEPM against Pseudomonas aeruginosa was the lowest of the drugs tested. MEPM showed low cross-resistant rate against both imipenem-resistant P. aeruginosa and ciprofloxacin-resistant P. aeruginosa. MEPM was active against most of the species tested in Gram-positive and anaerobic bacteria, except for multi-drug resistant strains including methicillin-resistant Staphylococcus aureus (MRSA), methicillin-resistant Staphylococcus epidermidis (MRSE). 2. The proportion of extended-spectrum beta-lactamase (ESBL) strains was 3.1% (4 strains) in Escherichia coli and 1.9% (2 strains) in Klebsiella pneumoniae. Carbapenems including MEPM were active against these ESBL strains. In conclusion, the results from this surveillance study suggest that MEPM retains its potent and broad antibacterial activity and therefore is a clinically useful carbapenem; at present, 7 years after available for commercial use.

Effect of osmolality on mucociliary transportability and rheology of cystic fibrosis and bronchiectasis sputum.

OBJECTIVE: Water is the main constituent of mucus, and its concentration is likely to be important in all aspects of mucus function, including ciliary clearance. The objective of this study was to investigate the effect of water content and osmolality of the mucus on mucociliary transportability. METHODOLOGY: Rheology and ciliary transportability of 10 sputum samples that had been subjected to various manipulations were measured using a mucus-depleted bovine trachea model. RESULTS: It was shown that addition of sodium chloride 0.2 Osmoles/kg (0.585% weight for weight) increased the transportability by 41% (P < 0.01). Evaporation of the sputum to 50% of its original weight caused a 118% increase in transportability (P < 0.0006), but iso-osmolal removal of 50% of the liquid with filter cards led to a non-significant, 25% increase in transportability. Parallel plate viscoelasticity was approximately doubled in both the evaporated and liquid-depleted samples, but was not changed by the addition of 0.2 Osmoles/kg of sodium chloride. The correlation between the osmolality of sputum and ciliary transportability (r = 0.54, P= 0.005) was better than the correlations between the viscosity (r = 0.21, P= 0.27) or elasticity (r = 0.23, P= 0.23) and ciliary transportability. CONCLUSIONS: These results suggest that the osmolality of sputum exerts a greater influence on mucociliary clearance than its viscoelastic properties.