The scope of lower respiratory tract infection

Diagnosis and management of pneumonia in children

BACKGROUND

This paper describes challenges in etiologic diagnosis and treatment of childhood community-acquired pneumonia and the means of addressing some of them.

MICROBIOLOGICAL DIAGNOSIS

From about one-third to two-thirds of cases of pneumonia can be attributed to a specific etiology depending on which culture, antigen detection and specialized serologic techniques, some of which are unavailable to clinicians, are used. Results of studies in which microbiologic causes have been sought confirm the importance of Streptococcus pneumoniae as the primary bacterial cause of pneumonia in infants and children. Viral etiologies become less prevalent and mycoplasmal and chlamydial infections become more prevalent with increasing age.

EMPIRIC TREATMENT

Because definitive information about causative pathogens is seldom available, treatment of pneumonia is most often empiric. Antibiotic therapy can be withheld in mildly ill, ambulatory patients in whom viral infection is likely. Most guidelines suggest initial treatment with orally administered amoxicillin or amoxicillin/clavulanate or with intravenous cefuroxime when patients require hospitalization. In May, 2000, the Centers for Disease Control-convened Drug-Resistant S. pneumoniae Therapeutic Working Group identified oral beta-lactams including cefuroxime axetil, amoxicillin and amoxicillin/clavulanate as appropriate options for first line therapy of community-acquired pneumonia in ambulatory adults and children.

CONCLUSIONS

New diagnostic techniques such as pneumococcal serologies and polymerase chain reaction testing have improved the ability to determine the microbiologic etiology of childhood pneumonia. Because these tests are not generally available, empiric treatment is necessary. Efforts to identify new intervention strategies, diagnostic tools, therapies and vaccines will be helpful in managing this disease.

Etiology and treatment of pneumonia

BACKGROUND

Lower respiratory tract infections are a common cause of morbidity among children. Among these infections pneumonia is the most serious illness and can be difficult to diagnose. The etiology of pneumonia is still partly unknown, primarily because of difficulty in obtaining adequate samples and lack of reliable diagnostic methods.

ETIOLOGY OF PNEUMONIA

Streptococcus pneumoniae is recognized as an important cause of pediatric pneumonia regardless of age in both the inpatient and outpatient setting. In developed countries S. pneumoniae probably accounts for 25 to 30% of cases of pediatric community-acquired pneumonia. Viruses (mostly respiratory syncytial virus) are responsible for approximately 20% of cases, and Chlamydia pneumoniae and Mycoplasma pneumoniae occur commonly in older children.

FUTURE CHALLENGES

Despite the effectiveness of antimicrobial therapy, the emergence of resistant bacterial pathogens has resulted in increased interest in developing more effective vaccines. If conjugate pneumococcal vaccines prove effective at eradicating carriage of pneumococci in the nasopharynx, immunization may be an important tool against the spread of pneumococcal disease. Future challenges include implementation of effective intervention strategies, production of simple diagnostic tools and development of effective vaccines.

Piperacillin/tazobactam in the treatment of community-acquired and nosocomial respiratory tract infections: a review

Investigators assessed the efficacy and safety of piperacillin/tazobactam therapy in a study of patients with community-acquired lower respiratory tract infections and a study of patients with nosocomial, severe lower respiratory tract infections. Piperacillin 4 g/tazobactam 500 mg was given intravenously every 8 h to 193 hospitalized lower respiratory tract infection patients for a minimum of 5 days. There was a favorable response rate of 97% and eradication of the causative pathogen was documented or presumed in 93% of patients. There was a low incidence of adverse experiences and the combination was well tolerated. Seventy-one intensive care patients with severe lung disease received 4 g piperacillin/500 mg tazobactam intravenously every 6 h; afterward they were given amikacin 7.5 mg/kg every 12 h. Minimum duration of treatment was 5 days. Therapy with piperacillin/tazobactam plus amikacin was well-tolerated, produced a 74% favorable clinical response rate, and eradicated the responsible pathogen in 70% of patients.