The radiographic resolution of Streptococcus pneumoniae pneumonia

Quality of published reports of the prognosis of community-acquired pneumonia

OBJECTIVE

To systematically assess the quality of published reports of the prognosis of community-acquired pneumonia using a formal quality assessment instrument.

DESIGN

Retrospective review of studies published during 1966-1991. ARTICLES: 108 articles related to the prognosis of community-acquired pneumonia retrieved by a computerized search.

INTERVENTION

All articles, blinded to author(s), journal title, year of publication, and study institution(s), were independently reviewed by two investigators using a ten-item quality assessment instrument designed to evaluate: 1) identification of the inception cohort (4 items), 2) description of referral patterns (1 item), 3) subject follow-up (2 items), and 4) statistical methods (3 items). Adherence to each of the ten individual quality items and an overall quality score were calculated for all articles and across three time periods.

MAIN RESULTS

Among all 108 articles that underwent quality assessment, 30 were published from 1966 to 1979, 61 from 1980 through 1989, and 17 from 1990 through 1991. The mean total quality score of all articles was 0.55 (range 0.22-0.90). There was a significant trend toward improvement in total quality scores over the three time periods (0.50 to 0.56 to 0.65; p < 0.001). However, several systematic errors in the study design or reporting of these studies were discovered throughout time: only 3.7% provided comparative information about nonenrolled patients, 28.7% determined whether the study institution was a referral center, 36.1% specified inclusion or exclusion criteria, and 45.5% used appropriate statistical analyses to adjust for more than one prognostic factor.

CONCLUSIONS

Despite improvement in overall quality of published articles, systematic errors exist in the design and reporting of studies related to the prognosis of community-acquired pneumonia. The quality assessment tool employed in this study could be used to guide the development of high-quality outcomes research in the future.

Diagnosing the cause of recurrent and persistent pneumonia in children

It is very important to note that safe and effective treatment of recurrent or persistent pneumonia in children is based on firmly establishing an etiologic diagnosis. Empiric treatment using repeated courses of antibiotics and hope is unlikely to yield cure or even good control of most of these processes and is likely to result in more cost to the patient's health and pocketbook. Applied in a staged and systematic way, the diagnostic tools currently available should enable the clinician caring for children to diagnose most of their patients with recurrent or persistent pneumonia. Consultation with a pediatric pulmonologist will generally speed the process and help with difficult or confusing cases. Because effective therapy is available but differs greatly from one etiology to another, early accurate etiologic diagnosis is extremely important. The prognosis for those with asthma generally is very good. But, delay in diagnosis of other causes of recurrent or persistent pneumonia can lead to irreversible pulmonary structural damage that ultimately can only be treated by lung transplantation, if at all.

Enhanced pneumonia resolution by inhalation of nitric oxide?

We present a patient with severe bacteraemic pneumococcal pneumonia associated with severe hypoxaemia, where nitric oxide (NO) 15-40 ppm was added to the inspired gas. Nitric oxide therapy improved gas exchange, reduced pulmonary vasoconstriction and peak airway pressure. The patient survived. We observed an unexpected rapid and complete disappearance of bilateral pulmonary infiltrates during the first 120 h of the 7-day NO inhalation period.

Utility of fiberoptic bronchoscopy in nonresolving pneumonia

Although fiberoptic bronchoscopy (FOB) has been traditionally used to evaluate nonresolving pneumonia, its efficacy is unknown. We, therefore, reviewed FOB in 35 consecutive patients who had (1) a roentgenographic infiltrate, (2) cough, (3) either temperature greater than 38.1 degrees C, leukocytosis, sputum production, (4) symptoms present for at least ten days, and antibiotic therapy for at least one week. Known lung cancer and AIDS were excluded. Fiberoptic bronchoscopy was diagnostic in 86 percent (12/14) in whom a specific cause was found. No patient had endobronchial cancer. Two patients with nondiagnostic FOB and persistent systemic symptoms had open lung biopsy specimens showing Wegener's granulomatosis and bronchiolitis obliterans with organizing pneumonia (BOOP). Twenty-one patients with nondiagnostic FOB had no final diagnoses other than community-acquired pneumonia. We conclude that FOB is extremely useful in finding a specific diagnosis for a nonresolving pneumonia when a specific diagnosis can be made. Fiberoptic bronchoscopy was most likely to yield a specific diagnosis in nonsmoking patients with multilobar infiltrates of long duration and could have been avoided in older, smoking, or otherwise compromised patients with lobar or segmental infiltrates with no decrease in diagnostic yield in our series.

Pulmonary telangiectasia without hypoxemia

We describe an elderly patient with an unusual presentation of hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber disease) involving the lung. He had recurrent "pneumonia" caused by massive hemorrhage from endobronchial telangiectases. When stable, he was normoxic, had no evidence of right-to-left shunting, and had mild pulmonary arterial hypertension. His pulmonary telangiectases may be isolated to the bronchial circulation. We report hemodynamic data and show the first photographs of endobronchial telangiectases.

Pneumococcal bacteremia. Update from an adult hospital with a high rate of nosocomial cases

Eighty-nine episodes of pneumococcal bacteremia were reviewed over a 66-month period at a Veterans Administration Medical Center. Forty-one percent of these episodes were nosocomial in origin, and 59% of the patients were elderly (60 years of age or older). Nosocomial infection occurred more often in the elderly (55%) compared to those less than 60 years of age (32%; P less than 0.05). Within the elderly group, those older than 75 years of age had a higher rate of nosocomial bacteremia than those 60 to 75 years of age (76 versus 44%; P less than 0.05). The clinical presentation of the elderly and younger groups was not significantly different. All but one patient had serious underlying diseases. Eighty-three percent of the episodes were due to pneumonia, and penicillin alone was prescribed for only 21% of all cases. The mortality rate directly due to the bacteremia was 22%, while the overall mortality during the hospitalization was 47%. In the elderly, the percentage of deaths due to infection was similar to the younger group, but overall mortality during the hospitalization was significantly higher in the elderly (74 versus 26%; P less than 0.01). Physicians showed poor recognition of the significance of pneumococcal disease, as demonstrated by inclusion of the diagnosis of pneumococcal infection or bacteremia in only 27% of the discharge summaries and by predischarge vaccination of only 7% (6 of 82) of those without previous pneumococcal vaccination. In conclusion, the rate of nosocomial pneumococcal bacteremia was high in a predominantly elderly male population; it may be appropriate to consider a hospital-based vaccine program in similar populations.

[Smoking and lower respiratory tract infection]

Cigarette smoking exerts deleterious effects not only on the respiratory tract, but also on the lung's parenchyma. The FEV is reduced in heavy chronic smokers. Persistent smoking has an unfavourable influence on mucociliary activity. According to the results of recent research almost 8 million people in the U.S. were suffering from chronic bronchitis in 1981. There is a direct correlation between the number of cigarettes smoked, over what period of time, and the incidence of chronic bronchitis. In studies with patients suffering from exacerbations of chronic bronchitis the most common bacterial pathogens found were Haemophilus influenzae, Streptococcus pneumoniae and Branhamella catarrhalis. Mycoplasma pneumoniae and certain viruses are counted amongst the non-bacterial pathogens. Antibiotics should be effective against such possible pathogens. The resistance of H. influenzae to ampicillin/amoxicillin is currently observed in at least 12% of cases, whilst H. influenzae is regularly observed to be resistant to erythromycin. Cefaclor, trimethoprim/sulphamethoxazole and amoxicillin/clavulanic acid offer satisfactory forms of treatment. Pneumonia caused by S. pneumoniae, H. influenzae, B. catarrhalis and Legionella pneumophila is often seen in smokers and patients with COLD. Haemocultures should be prepared for all hospitalized patients. Penicillin G and/or V is the agent of choice. Cefaclor or trimethoprim/sulphamethoxazole can be given to counter beta-lactamase producing H. influenzae whilst cefaclor, erythromycin, tetracycline or trimethoprim/sulphamethoxazole are used for the treatment of B. catarrhalis infections. In Legionella infections erythromycin is the preferred treatment. A combination of erythromycin and cefamandole or ceftriaxone is indicated for empirical management. Patients with COLD should be immunised with pneumococcus and influenza vaccines.

Antibiotic therapy in pneumonia: a comparative study of parenteral and oral administration of penicillin

An open, randomized study of treatment of radiologically verified community-acquired pneumonia is described. 33 patients were treated with phenoxymethylpenicillin orally in an average dose of 2 g every 8 h, and 36 patients were treated intravenously with benzylpenicillin 3 g every 8 h. When temperature was normalized the antibiotic dose was reduced in both groups to oral phenoxymethylpenicillin in an average dose of 1 g every 8 h. 24 and 26 patients in respective groups completed 10 days of therapy. No statistically significant differences between the two groups were found when compared for duration of fever, hospital stay, CRP, ESR, leukocyte counts and X-ray normalization. In spite of the low number of patients included in this study it gives a clear indication that treatment of pneumonia with penicillin by the oral route results in the same outcome as parenteral treatment when patients suffering from vomiting, diarrhoea and severe illness with respiratory distress are excluded. In addition, oral treatment is cheaper than parenteral and more simple to manage.

Community-acquired pneumonia caused by mixed aerobic bacteria

Mixed bacterial pneumonia caused by organisms other than anaerobes has been infrequently reported. We describe six cases and review the literature. Two patients had co-infection with S pneumoniae and L pneumophila. Two were infected with S pneumoniae and K pneumoniae and the others simultaneously harbored M tuberculosis and N asteroides. The first two sets of patients had bacteria isolated from usually sterile sites (blood and lung), while the latter harbored repeatedly isolated organisms not usually felt to be part of the normal respiratory flora. Mixed infection may help explain the substantial mortality still seen from pneumonia. This is especially true if Legionella, mycobacteria, or Nocardia species are encountered where routine smears and cultures may not aid in the diagnosis. Poor clinical response to specific antibacterial therapy in pneumonia should trigger further investigation for other potential pathogens.

Pleural effusions. 2. Definitive evaluation of the exudate

Based on the current literature, the following steps seem reasonable in evaluating a pleural effusion: document the presence, location, and approximate volume of pleural fluid; decide clinically on the likelihood of an exudative effusion; if clinical evaluation suggests an exudative effusion, perform a thoracentesis and obtain fluid for diagnostic evaluation; perform the necessary tests to characterize the effusion as a transudate or an exudate; if a transudate exists, normally do not perform further tests on the effusion; if an exudate exists, perform selected tests to narrow the differential diagnosis; if this evaluation is undiagnostic, consider closed pleural biopsy; if the diagnosis remains unclear after two closed biopsies, consider pleuroscopy with biopsy or open pleural biopsy at the time of a thoracotomy.

Community-acquired pneumonia requiring hospitalization. Is it different in the elderly?

The authors studied 138 patients, 57 of whom were younger than 65 years of age and 81 who were 65 years of age and older, with community-acquired pneumonia to determine whether or not such pneumonia is different in the elderly and to define how such patients are investigated and treated. Pneumonia in the elderly was characterized by a higher mortality, 30 v 10%; more likely to be of unknown etiology, 54 v 30%; and more likely to show radiographic progression after the patient had been admitted to the hospital, 48 v 11%. In addition, elderly patients were more likely to be afebrile when admitted, 57 v 26%. Twenty-seven etiologic categories were present in 77 patients in whom a cause for the pneumonia was established. Streptococcus pneumoniae accounted for 9.4% of the pneumonia overall and for 27% of the pneumonia among patients who had sputum cultures performed before antibiotic therapy. The diagnostic yield was 11.6% for blood cultures, 38.2% for sputum cultures, 2.3% for throat washing, and 22.1% for serological studies. Twenty-seven percent of patients were receiving antibiotics of the time of admission to the hospital. Most (79%) received more than one antibiotic after admission. This study indicates that community-acquired pneumonia is a serious illness and that an algorithm approach to diagnosis and treatment of such pneumonia is necessary.

Community-acquired lower respiratory tract infections. Prevention and cost-control strategies

The treatment of patients with community-acquired pneumonia can be expensive, particularly if care is hospital-based. Cost control begins with prevention. Current influenza vaccines are about 80 percent protective, but grossly underused. Amantadine and rimantadine are effective chemoprophylactic agents against influenza A, but also underused. Use of pneumococcal vaccine is controversial, but patients who are thought to be at increased risk should be immunized. Management decisions in patients with pneumonia that have major cost implications include the need for hospitalization and choice of diagnostic tests and therapy. The need for hospitalization has not been well studied. In general, young patients with atypical pneumonia are treated at home, whereas older patients with complicating illnesses are admitted to hospitals. Length of hospitalization has decreased in recent years. Diagnostic tests have traditionally emphasized chest roentgenography, Gram staining of the sputum, and sputum culture. Published data suggest that a Gram staining of the sputum can be useful. Sputum cultures are frequently confusing and should be discontinued. Intermittent positive pressure breathing treatments have no value, and chest physiotherapy is unnecessary for most patients.

Community-acquired bacterial pneumonia in the elderly

Pneumonia remains the leading infectious disease-related cause of death among the elderly. Streptococcus pneumoniae is the most frequent pathogen isolated from aged individuals with community-acquired pneumonia. Other common bacteria that cause this disease include Haemophilus influenzae and Legionella pneumophila. Manifestations of pneumonia in the elderly can be subtle and result in delayed recognition and treatment. Gram stain evaluation and culture of non-contaminated expectorated sputum remain the conventional techniques to guide initial antibiotic selection. While the presence of a new infiltrate on chest X-ray confirms the clinical diagnosis of pneumonia, the radiographic appearance of the infiltrate cannot accurately define the etiologic agent. Specific therapeutic measures include administration of appropriate antibiotics, correction of fluid and electrolyte imbalances, nutritional support and treatment of concomitant disorders. Preventive measures include use of influenza vaccine, amantadine and pneumococcal vaccine.

Comparative radiographic features of community acquired Legionnaires' disease, pneumococcal pneumonia, mycoplasma pneumonia, and psittacosis

The features of the chest radiographs of 49 adults with legionnaires' disease were compared with those of 91 adults with pneumococcal pneumonia (31 of whom had bacteraemia or antigenaemia), 46 with mycoplasma pneumonia, and 10 with psittacosis pneumonia. No distinctive pattern was seen for any group. Homogeneous shadowing was more frequent in legionnaires' disease (40/49 cases) (p less than 0.005), bacteraemic pneumococcal pneumonia (25/31) (p less than 0.01) and non-bacteraemic pneumococcal pneumonia (42/60) (p less than 0.05) than in mycoplasma pneumonia (23/46). Multilobe disease at presentation was commoner in bacteraemic pneumococcal pneumonia (20/31) than in non-bacteraemic pneumococcal pneumonia (15/60) (p less than 0.001) or legionnaires' disease (19/49) (p less than 0.025). In bacteraemic pneumococcal pneumonia multilobe disease at presentation was associated with increased mortality. Pleural effusions and some degree of lung collapse were seen in all groups, although effusions were commoner in bacteraemic pneumococcal pneumonia. Cavitation was unusual. Lymphadenopathy occurred only in mycoplasma pneumonia (10/46). Radiographic deterioration was particularly a feature of legionnaires' disease (30/46) and bacteraemic pneumococcal pneumonia (14/27), and these groups also showed slow radiographic resolution in survivors. Radiographic resolution was fastest with mycoplasma pneumonia; psittacosis and non-bacteraemic pneumococcal pneumonia cleared at an intermediate rate. Residual intrapulmonary streaky opacities remained in over a quarter of survivors from legionnaires' disease (12/42) and bacteraemic pneumococcal pneumonia (5/19).

Erythromycin compared with a combination of ampicillin and amoxycillin as initial therapy for adults with pneumonia including Legionnaires' disease

In a double blind trial erythromycin was compared with a combination of ampicillin and amoxycillin for treating adults admitted to hospital with primary pneumonia. The clinical course of 42 patients treated with ampicillin and amoxycillin was similar to that of the 49 in the erythromycin group. Fall in temperature, symptomatic recovery and radiographic improvement were similar (two-thirds made an uncomplicated recovery). Infusion-related phlebitis was more common with erythromycin. Otherwise adverse reactions were unusual. The outcome was related principally to the cause of the pneumonia with bacteraemic/antigenaemic pneumococcal pneumonia, Legionnaires' disease, other bacterial pneumonias and psittacosis having a poor prognosis. Both forms of antibiotic therapy gave similar results but we suggest that a combination of erythromycin with ampicillin may be logical initial treatment for severe pneumonia of unknown cause.

Needle aspiration of the lung in complex pneumonias

In 39 patients with treated unresponsive pneumonia complicated by life-threatening underlying disease, direct needle aspiration of the lung was performed to establish a cause. An infectious agent was detected in 18 patients (46 percent), a nonbacterial cause was found in one, and cure of a recent infection was substantiated in six patients. An incorrect diagnosis was made in seven patients (one false-positive and six false-negative), and an indeterminant answer was obtained by needle aspiration in seven. Serious complications occurred in 11 patients, most commonly in those who had hypoxia or thrombocytopenia, but no morbidity occurred in 22 patients. The diagnostic yield allowed effective rational therapy to be selected for multiple potential pathogens in 12 patients and detected pathogens not suspected in six instances. The technique compares favorably to other invasive techniques for establishing definitive information in this group of seriously ill patients.