Name
CHLAMYDIAL PNEUMONIA
DESCRIPTION
DETAIL
MAY BE CAUSED BY THREE SPECIES : 1. C. PSITTACI 2. C. PNEUMONIAE 3. C. TRACHOMATIS -------------------------------------------------------------------------- DIFFERENTIAL DIAGNOSIS: - Consider other common bacterial respiratory pathogens, including Streptococcus , Bordetella , Haemophilus , Klebsiella , Mycoplasma and Legionella speciesβ’ Leukocyte count usually normal or low β’ Sedimentation rate often moderately elevated β’ Sputum usually negative by gram stain and routine culture * C. PSITTACI INFECTION : SINGLE SERUM TITERS ARE INSENSITIVE & NONSPECIFIC. CONFIRMATION WITH PAIRED & CONVALESCENT SERA IS NECESSARY - ISOLATION OF ORGANISM BY CULTURE - FOUR FOLD RISE IN COMPLEMENT-FIXING OR MICROIMMUNOFLUORESCENCE ANTIBODIES ( MIF) TO A RECIPROCAL TITER OF 32 OR GREATER BY PAIRED SERA AT LEAST 2 WEEKS APART OR - DETECTION OF IMMUNOGLOBULIN M (IGM) ANTIBODY AGAINST C. PSITTACI BY MIF. C. PNEUMONIAE : - SPECIFIC MIF ANTIBODIES - 4 FOLD INCREASE - C. PNEUMONIAE SPECIFIC IGG & IGM - INCREASED - WBC COUNT - GENERALLY NOT INCREASED - S. ALKALINE PHOSPHATASE - MAY BE ELEVATED - PCR - CELL CULTURE * C. TRACHOMATIS : PRESENCE OF CHLAMYDIAL INCLUSIONS OR ELEMENTARY BODIES ON GIEMSA-STAINED SMEARS OF CONJUNCTIVA OR NASOPHARYNX - ANTICHLAMYDIAL IGM TITER - ELEVATED - SERUM IMMUNOGLOBULIN LEVELS - ELEVATED * IMAGING: β’ Chest radiograph may be abnormal even in clinically mild disease β’ Variable radiographic abnormalities include unilateral and bilateral infi ltrates and pleural effusions. Single, subsegmental infi ltrate is common. * DIAGNOSTIC PROCEDURES: Definite diagnosis of acute infection requires a positive culture or PCR or a four-fold rise in antibody titer. Very high antibody titer or antibody in the IGM fraction suggests a recent infection.
TYPENOTES
RISK FACTORS: Outbreaks have occurred among groups of military recruits, university students, students and nursing home residents. Sporadic cases often. No known animal hosts. Associated with ac. resp. exacerbation in children with cystic fibrosisMedical Care: " C psittaci o Tetracycline or doxycycline is the treatment of choice. Continue treatment for 10-21 days. A longer course to prevent relapse is controversial. o Erythromycin is the alternative treatment, but this drug may be less efficacious in severe cases. " C pneumoniae o Doxycycline is the treatment of choice except in children younger than 9 years and pregnant women. Treatment should be continued for at least 10-14 days after defervescence. If symptoms persist, a second course with a different class of antibiotics is usually effective. o In outpatient settings, use doxycycline (100 mg PO bid) or tetracycline hydrochloride (500 mg PO qid). o In inpatient settings, use doxycycline hyclate (100 mg IV bid). o Alternatives include erythromycin (500 mg PO/IV qid) and newer macrolides such as azithromycin (500 mg PO/IV qd for 7-10 d) and clarithromycin (1 g PO qd [Biaxin XL] or 500 mg PO bid for 10 d). Newer macrolides are better tolerated than erythromycin. Shorter courses of the newer macrolides appear to be effective. o Telithromycin is the first antibiotic in a new class called ketolides and is approved by the US Food and Drug Administration for C pneumoniae pneumonia. It is more expensive than doxycycline. Telithromycin is a potent inhibitor of CYP3A4 and can cause potentially dangerous increases in serum concentrations of simvastatin, lovastatin, atorvastatin, midazolam, and other drugs. If telithromycin is used, statins should be withheld for the duration of therapy. o Fluoroquinolones, including levofloxacin (500 mg PO/IV qd for 10-14 d) and moxifloxacin (400 mg PO/IV qd for 10-14 d), also have some activity, although less than that of tetracyclines or macrolides. Gatifloxacin is no longer marked in the United States. " C trachomatis infant pneumonia o Treatment for infant pneumonia mirrors the treatment for conjunctivitis. The efficacy is approximately 80-90%. o Treat with erythromycin (50 mg/kg/d PO divided q6h for 10-14 d). o Doxycycline is contraindicated in children younger than 9 years. Surgical Care: Valve replacement may be required for patients with endocarditis. DRUG TREATMENT : 1. ANTIBIOTICS : - TETRACYCLINE - DOXYCYCLINE - ERYTHROMYCIN - CLARITHROMYCIN - AZITHROMYCIN - LEVOFLOXACIN PATIENT MONITORING : Weekly until well, for response to treatment and resolution of radiographic abnormalities PREVENTION/AVOIDANCE: β’ Transmission presumably via respiratory secretions. Avoid infected persons. β’ Hand washing POSSIBLE COMPLICATIONS: β’ Reactive airway disease β’ Erythema nodosum β’ Otitis media β’ Endocarditis β’ Myocarditis β’ Pericarditis β’ Sarcoidosis β’ Meningitis/encephalitis β’ Reactive arthritis β’ Acute chest syndrome in sickle cell disease EXPECTED COURSE/PROGNOSIS: β’ Resolution of cough and malaise often requires several weeks or longer β’ Chronic bronchospastic disease has been reported following acute infection β’ Persistent or relapsed symptoms may respond to second course of antibiotics
RELATED DISEASE
Not Available Disease
DISEASE
INVESTIGATION
SERUM ALKALINE PHOSPHATASE, SERUM IGG, SERUM IGM, X-RAY CHEST P.A. VIEW( NORMAL ), COMPLETE BLOOD COUNT, SPUTUM FOR GRAM STAINING, SPUTUM FOR CULTURE & SENSTIVITY TEST