Comparison of DNA targets for amplification by polymerase chain reaction for detection of Mycobacterium tuberculosis in sputum.

PCR assays for detection of Mycobacterium tuberculosis were compared using three different primer pairs to amplify fragments of IS 6110, pab and mtp 40 genes. The amplified products were detected by gel electrophoresis. The detection limit of PCR assay for amplification of IS 6110, pab and mtp 40 genes was 10,100 and 100 femtograms of purified M. tuberculosis DNA, respectively. Fifty-six smear-positive sputum samples were tested for the sensitivity of detection. Two sputum specimens contained inhibitors that were not removed after treatment. Of 54 specimens, 53 was positive for M. tuberculosis and one was positive for mycobacteria other than Mycobacterium tuberculosis (MOTT) by culture method. The one that grew MOTT was PCR-negative. Of 53 culture-positive found to contain M. tuberculosis, amplified products were detected in 47 (90%), 28 (53%) and 17 (30%) samples in which the target for amplification was IS 6110, pab and mtp 40 genes, respectively. This study confirms the potential of IS 6110 amplification by polymerase chain reaction for rapid detection of M. tuberculosis in clinical specimens.

Prognostic factors in patients hospitalized with pneumonia.

Prognostic factors in patients hospitalized with pneumonia was analysed from 526 non-immunocompromised host patients who were admitted to the Medical Department of Chulalongkorn Hospital during the period of January 1987 to December 1991. The overall mortality was 30.5 per cent. The causes of death were 12.7 per cent of progressive or uncontrolled pneumonia, 10.1 per cent of underlying diseases and 7.2 per cent of complications of assisted ventilation. Patients aged 60 or older than 60 years, abnormal host, mental status changes, respiratory failure, shock, bronchopneumonia, g-ve pneumonia had significantly higher mortality than those who had no such conditions. Patients with pneumonia who had respiratory failure and shock had highest mortality at 70.2 and 85.1 per cent, respectively. Our study indicated that the presence of pleuritic chest pain and pleural effusion had a favourable effect on the outcome.

Pneumonia with pleural effusions.

One hundred and forty three among five hundred and twenty-six cases of bacterial pneumonia in adults (27.2%) who had pleural effusion (parapneumonic effusion) admitted to Chulalongkorn Hospital during the period January 1987 to December 1991 were analyzed. There were 40 cases with effusion that was less than 10 mm thick on chest decubitus film, 44 cases of uncomplicated exudative phase, 40 cases of complicated exudative phase (early empyema) and 19 cases of empyema. Most patients in our study required thoracocentesis (72%), had early empyema and emyema (41.3%) as well as high incidence of positive organisms on Gram stain in pleural fluid. This indicates that our patients may have had a prolonged clinical course before coming to the hospital. About half of our patients had pleuitic chest pain or signs of pleural effusion. Among the various stages of parapneumonic effusion, the empyema group had the most delayed response to treatment and needed intercostal drainage for twice the duration of the early empyema group (15.69 vs 7.55 days). The overall mortality was 22.4 per cent. Factors associated with death were advanced age, hospital acquired and broncho-pneumonia, abnormal host, no pleuritic chest pain, no signs of consolidation, respiratory failure, shock and complications of assisted ventilation.

Bacterial pneumonia in the elderly.

Five hundred and twenty-six cases of bacterial pneumonia in adults admitted to Chulalongkorn Hospital during the period January 1987 to December 1991 were studied, comparing the elderly aged > or = 60 years (241 cases) with the nonelderly < 60 years of age (285 cases). The study indicates that there was a significantly increased number of community and hospital-acquired pneumonia in the elderly than previously reported. Pneumonia in the elderly might present with no fever, no cough no signs of parenchymal infiltration, but significant mental changes. There was a higher incidence of pleural involvement, but lower incidence of septic shock in the non-elderly than the elderly, which suggests that the nonelderly had better systemic resistance against bacterial infection than the elderly. There was no significant difference in complete blood count between the two groups. However, sputum specimens to be collected through endotracheal tube and Gram-negative bacilli on Gram stain were found more in the elderly than the non-elderly. The elderly had more respiratory failure requiring mechanical ventilation, septic shock, and had higher mortality than the non-elderly. They also required longer duration of treatment and hospitalization. There were parameters which indicated the high-risk factors for mortality among the elderly. These included hospital-acquired pneumonia, bronchopneumonia, Gram-negative pneumonia, abnormal status of host, sputum specimens requiring collection by suction, respiratory failure and septic shock.

Community- and hospital-acquired pneumonia in medical intensive care unit.

Seventy-four cases of pneumonia admitted to the Medical Intensive Care Unit of Chulalongkorn Hospital from January 1986 to December 1988 were analyzed. There were 52 males and 22 females with 46, 26 and 2 cases of community-, hospital- and combined-acquired pneumonia, respectively; the average age on admission was 58 +/- 18.1 years. The majority of the patients had abnormal host or underlying pulmonary diseases. Most of the cases with community-acquired pneumonia were admitted to the ICU because of respiratory failure (85%) and most of the cases with hospital-acquired pneumonia had ventilator-associated pneumonia (71.4%). The dominating pathogens in community- and hospital-acquired pneumonia were Gram-positive and Gram-negative organisms, respectively. There were no significant differences in initial clinical manifestations, laboratory data, complications, between the two groups. However, the duration on antibiotic, respirator, leukocytosis and stay in hospital were significantly longer in hospital acquired than community acquired pneumonias. Overall mortality was 63.5 per cent, the causes of which were progressive or uncontrolled pneumonia and mechanical ventilation complications in 37.8 and 25.7 per cent of the cases, respectively. High-risk factors of the non-surviving groups included pneumonia on assisted ventilation, mechanical ventilation complications, shock and the presence of Gram-negative bacilli. Our study indicates that the patients required assisted ventilation because of the severity of the underlying pulmonary conditions rather than the extent of the pneumonia itself. Gram-negative pneumonia predisposed the patients requiring mechanical ventilation to develop complications. The duration on mechanical ventilation, ICU admission and hospitalization were 13.84, 13.21 and 29.08 days, respectively.

Mechanical and non-mechanical ventilation of respiratory failure in chronic obstructive pulmonary disease.

Among 182 episodes with ARF (PaCO2 > 50 torr) in 400 episodes of COPD patients who were admitted to Chulalongkorn Hospital during the period 1982 to 1986, despite conservative treatment, 66 developed severe acute respiratory failure requiring assisted ventilation. Patients with a history of chronic cough, pneumonia as a precipitating factor and more severe ARF on admission, as indicated by palpitation, headache, cyanosis, alteration of consciousness, cor-pulmonale and decompensated acidosis (pH < 7.30), were likely to require mechanical ventilation. Indications for mechanical ventilation were carbon dioxide narcosis (43 episodes), severe hypoxemia despite on a high FIO2 (one episode), various combination parameters of respiratory muscle fatigue, cardiovascular instability (22 episodes). The major complications of mechanical ventilation were pneumonia, sepsis, pneumothorax, UGI bleeding of 16, 8, 5 and 9 episodes, respectively. The average duration of assisted ventilation and hospitalization were 15.8 and 19.02 days, respectively. The mortality rate was 50 per cent in the mechanical ventilation group compared with 9.8 per cent in the non-mechanical ventilation group. Increased mortality rate was found in those with pneumonia as the precipitating factor (68.4 vs 14.3%, respectively, in comparing the two groups). Complications of mechanical ventilation, which included pneumonia, sepsis, fluid overload, hyponatremia and persistent acidosis, were high-risk factors for the non-surviving group.

Spontaneous pneumothorax in chronic obstructive pulmonary disease.

There were 34 episodes of pneumothorax out of 400 episodes of COPD (i.e. 8.5% of the total) among patients who were admitted to Chulalongkorn Hospital during the period 1982 to 1986; the episodes of pneumothorax occurred among 22 males and one female, with the average age on admission being 64.0 +/- 8.5 years. All patients had a long history of smoking (average 40 years) with a history of recurrent pneumothorax (47.8%) and two episodes of pneumothorax per patient. Since only about one third of our patients had chest pain or positive signs of pneumothorax on physical examination, the possibility of pneumothorax should be considered in every patient who develops sudden and increasing shortness of breath, especially during mechanical ventilation, or even in association with other obvious precipitating factors, e.g. URI. With regard to complications, there were eight, four, two, two and five episodes of severe respiratory failure requiring assisted ventilation, tension pneumothorax, bilateral simultaneous pneumothorax, pneumomediastinum with subcutaneous emphysema, and plural effusion, respectively. The death rate was 23.5 per cent. Patients who had a pneumothorax requiring assisted ventilation or who developed a pneumothorax during assisted ventilation had a grave prognosis because of multiple complications from mechanical ventilation. Two episodes with minimal pneumothoraxes achieved re-expansion after conservative treatment. The treatment required 3.3 days for the lung to fully expand, 9.6 days when the air-leak stopped and the duration of tube drainage was 10.8 days. Our study indicates that the longer the duration of lung collapse the longer the time required for re-expansion of the lung.(ABSTRACT TRUNCATED AT 250 WORDS)

Chronic obstructive pulmonary disease at Chulalongkorn Hospital: an analysis of 400 episodes.

Four hundred episodes of COPD among patients admitted to Chulalongkorn Hospital between 1982 and 1986 were analyzed. There were 193 males and 45 females with 325 and 75 episodes of admission, respectively; the average age on admission was 68.4 +/- 0.5 years. The most significant associated underlying factor was cigarette smoking in 94 per cent of the cases, with the patients smoking an average of 1.15 packs of cigarettes per day for 43 years. In our study, 26.8 per cent of the patients had a cough, with the average age at onset being 47.4 +/- 2.1 years. The most common clinical manifestation was dyspnea with 58.5, 35.2 and 0.5 per cent having dyspnea functional class II, III, IV and with the average age at onset being 61.1 +/- 0.7, 66.6 +/- 0.7 and 71.0 +/- 1.0 years, respectively. An important manifestation on admission was dyspnea functional class III and IV, which were present in of 89 per cent of the cases. The main precipitating factors which led to the patients' admission were upper respiratory tract infection, pneumonia, bronchospasms and congestive heart failure, which accounted for 48.0, 10.0, 8.5, 31.8 and 18.3 per cent of the cases, respectively. With regard to these complications, there were 16.5, 48.3, 31.1 and 12.5 per cent of the patients who suffered respiratory failure requiring assisted ventilation, corpulmonale, polycythemia and peptic ulcer, respectively. Arterial blood gas on admission revealed a pH level of 7.36 +/- 0.1, pCO2 of 53.3 +/- 23.7 torr, and PO2 of 54.2 +/- 19.9 torr.(ABSTRACT TRUNCATED AT 250 WORDS)

Pulmonary nocardiosis in Chulalongkorn Hospital.

From 1982 to 1988, 20 patients with pulmonary nocardiosis were diagnosed at the Department of Medicine, Chulalongkorn Hospital University. The infection was found to be common in immuno-compromised hosts particularly in patients who were suffering from lymphoreticular malignancy, systemic lupus erythematosus, nephrotic syndrome, pulmonary alveolar proteinosis and in patients who were receiving corticosteroids. The clinical manifestations were usually nonspecific. Diagnosis of pulmonary nocardiosis in cases who presented with a short duration of fever and productive cough was often delayed because they were considered to have acute bacterial pneumonia. The findings on chest roentgenogram were nonspecific as nonhomogeneous airspace infiltrates, cavitary lesions, nodule, or miliary infiltrates. The complete blood count frequently showed leukocytosis and neutrophilia. The diagnosis of nocardiosis was suspected if the staining of specimens obtained from the lesions showed typically weakly gram-positive and modified acid-fast branching filament organism and the diagnosis was confirmed by culture. The skin and the central nervous system were the most common hematogenous disseminations. Sulfamethoxazole and trimethoprim in combination were the drugs of choice. The treatment for a minimum of 6 months was appropriate in order to prevent relapse. Poor prognostic factors in nocardiosis were acute infection, Cushing's disease; and disseminated infection involving the central nervous system.

Status asthmaticus: an analysis of 560 episodes and comparison between mechanical and non-mechanical ventilation groups.

An analysis and comparison of 286 adult patients involving 560 episodes of status asthmaticus admitted to the Medical Service of Chulalongkorn Hospital during the years 1984 through 1988 were examined. There were 58 patients who required mechanical ventilation 75 times compared with 228 patients with 485 episodes of attack who did not require the use of mechanical ventilation. The increased risk factors for status asthmaticus among those who required assisted ventilation were as follows: younger age at onset of asthma, younger age of severe attack, chronic asthma (especially unstable asthma), previous history of intubation and mechanical ventilation, shorter duration of severe attack and extremely severe attack in the sitting position before arriving at the emergency room, receiving beta 2 adrenergic inhaler, mistakenly taking beta blockers, high fever (over 38 degrees C) as a result of respiratory tract infection, increased initial pulse rate (over 125 beats/minute) and white blood cell count of over 16,000/mm3, and pneumothorax on admission. Simple asthma and history of taking franol or tedral in status asthmaticus indicated a low risk for mechanical ventilation. The taking of glucocorticoids did not pose a risk to status asthmaticus requiring mechanical ventilation.

Relationships between pleural fluid pH, PCO2 to pleural fluid PO2, amylase, protein, glucose and white cells in tuberculous and malignant effusions.

The relationships between pleural fluid pH and PO2 to pleural fluid PO2, amylase, protein, glucose, white cell count were examined in 110 cases of tuberculous and 140 cases of malignant pleural effusions. Pleural fluid amylase concentrations of 200 or more units/ml indicated malignant effusions rather than tuberculous effusions with a specificity of 92.7 per cent and sensitivity of 27.1 per cent. There was evidence which suggested that the increasing pleural fluid amylase concentrations were due to the excessive leakage of serum amylase into the pleural cavity secondary to the break-down of capillaries by tuberculosis and malignancy as well as the production of amylase by tumor cells invading the pleura. The decreasing pleural fluid pH and increasing pleural fluid PCO2 had a significant linear relationship with decreasing fluid PO2, increasing pleural fluid protein and decreasing fluid glucose. These indicated a leakage of serum protein into the pleural cavity and the over-utilization of glucose relative to the transport defect of low pleural fluid glucose concentrations in the acidotic fluid of tuberculous and malignant effusions. No relationship between pleural fluid pH and PCO2 to pleural fluid and white cell count was found in the present study.

Mechanical ventilation in status asthmaticus: experience with 75 episodes.

Mechanical ventilation in 75 out of 560 status asthmaticus episodes during a five-year period (1984-1988) at Chulalongkorn Hospital were analyzed. There were 58 patients with an average age of onset of first asthmatic attack of 18.5 years and an average age when requiring mechanical ventilation of 33 years, which is significantly younger than among those who did not require assisted ventilation. At the time of intubation, four patients were in sudden unexpected arrest and 19 patients were urgently ventilated because of respiratory muscle fatigue or carbon dioxide narcosis; the remaining 52 patients required elective mechanical ventilation. The arterial blood gas of 52 patients revealed a pH of 7.11 +/- 0.66, PaCO2 of 58.0 +/- 5.5 mmHg, and HCO3 of 15.0 +/- 5.8 mEg/L. Controlled mechanical ventilation was maintained for a mean of 38.68 hours. Fifty-one patients required intravenous diazepam (average dose = 24.3 mg) and 37 required morphine (average dose = 11.1 mg) for good syncronization in controlling mechanical ventilation. Pneumothorax was the most common complication with four, nine and one episodes occurring prior to, during and after assisted ventilation, respectively. Four, one and two patients developed the complications of pneumonia, atelectasis of the left lung due to mucous plugging and upper gastrointestinal hemorrhage, respectively. There were six patients who died of complications: four of brain anoxia, one of pneumothorax and another of unexplained cause.

Fiberoptic bronchoscopy in diagnosis of patients with suspected active pulmonary tuberculosis.

Patients suspected of having active pulmonary tuberculosis, in whom acid-fast bacilli (AFB) are not demonstrated on sputum direct smear, present a difficult diagnostic and therapeutic problem. Flexible fiberoptic bronchoscopy is a useful procedure in evaluating these patients. Within five years, during the period of January 1983 to December 1987, 112 patients who were suspected of having active pulmonary tuberculosis underwent fiberoptic bronchoscopy. The diagnosis of pulmonary tuberculosis was established by using this procedure in 76 per cent of cases. Immediate diagnosis were made from microscopic specimens obtained from bronchoscopy in 38 of 65 patients (58%). It is concluded that fiberoptic bronchoscopy should be performed in evaluating patients with negative smears for AFB who are clinically suspected of having tuberculosis before initiating a trial of antituberculous drugs. The technique is safe and markedly efficacious in making an immediate diagnosis and uncovering other diseases that present themselves like tuberculosis.

Amikacin pharmacokinetics in plasma and pleural fluid.

The pharmacokinetics of amikacin in plasma and pleural fluid were studied in nine adult patients with pleural effusions. After a single intravenous bolus of 7.5 mg of amikacin per kg, concentrations in plasma and pleural fluid were measured by fluorescence polarization immunoassays. Pleural fluid pH and PCO2 were also measured. The plasma pharmacokinetics was similar to other studies. However, in the present study the central compartment was significantly greater than the peripheral compartment. Our study suggested that there might be a significant binding of amikacin to the inflamed and/or damaged pleural as suggested by the significant correlations between the apparent volumes of distributions of central and total compartments with pleural fluid pH and PCO2. In pleural fluid, amikacin kinetics followed a large reservoir model with maximum concentration, 4.34 +/- 0.50 mg/L, occurring at 5.64 +/- 0.67 hours post-dose and its half-life was 13.50 +/- 2.93 hours. This concentration was lower than the minimal inhibitory concentration (MIC) for most of the sensitive strains of Gram-negative bacilli and therefore the antibiotics should be given as early as possible for gram-negative pneumonia.