Summary
Usage Community acquired pneumonia (CAP) is a common condition that presents in the outpatient setting (primary care and emergency care) with a hospitalization rate of approximately 2% in ages ≥ 65 years and is associated with a 30-day mortality rate of 5% in hospitalized patients (Womack & Kropa, 2022). Further, Womack & Kropa highlight that in 11% of patients a bacterial pathogen was identified, 23% of patients a viral pathogen and 62% of patients no organism was identified. (Note: These studies were conducted before the COVID-19 pandemic.) Diagnosis of community acquired pneumonia (CAP) is usually made with a combination of history, physical exam, and findings on chest x-ray, lung US or chest CT scan. Clinicians are encouraged to use both their clinical judgement and a validated clinical prediction rule to determine the need for hospitalization in patients with CAP (Armstrong, 2020). The Pneumonia Severity (PSI) Pneumonia Patient Outcomes Research Team (PORT) prediction rule is a well-validated risk stratification tool that can assist clinicians in the outpatient setting with determining disposition (inpatient versus outpatient). However, validated clinical prediction rules, like the PSI/PORT and CURB-65, do not effectively determine the level of care required (Armstrong, 2020). The American Thoracic Society (ATS) and the Infectious Diseases Society of America (IDSA) criteria for severe CAP is preferred to predict ICU admission.¹ Low-quality evidence suggests the PSI/PORT may outperform CURB-65. Armstrong (2020) reports the PSI/PORT can underestimate the severity of illness among younger patients, but it has higher discriminative power in predicting mortality and a lover false-positive rate then the CURB-65. ¹Statement on COVID-19 (Armstrong, 2020): "Editor's Note: This ATS/IDSA guideline was produced before the COVID-19 pandemic, which has altered the diagnosis and management of lower respiratory tract infections. The current version of this guideline limits testing and antiviral treatment in patients with influenza, and we expect testing for and treatment of severe acute respiratory syndrome coronavirus 2 infection to become a long-standing element of standard pneumonia care. Although the IDSA has published initial guidelines for management of COVID-19, the situation is evolving rapidly (https://www.idsociety.org/practice-guideline/covid-19-guideline-treatment-and-management).Free information on COVID-19 is available from American Family Physician at https://www.aafp.org/journals/afp/explore/COVID-19.html and Essential Evidence Plus at http://www.essentialevidenceplus.com/content/eee/904.". Summary The Pneumonia Severity (PSI) Pneumonia Patient Outcomes Research Team (PORT) prediction rule is a well-validated risk stratification tool that can assist clinicians in the outpatient setting with determining disposition (inpatient versus outpatient). Diagnosis of community acquired pneumonia (CAP) is usually made with a combination of history, physical exam, and findings on chest x-ray, lung US or chest CT scan. Intended for immunocompetent adults who have not recently traveled internationally. Rule criteria CriteriaPointsAge1 point per yearSexMale (0) Female (-10)Nursing home resident10Neoplastic disease¹30Liver disease history²20Cerebrovascular disease history³10Renal disease history⁴10Liver disease history⁵20Altered mental status⁶20Pulse ≥ 125 beats/min10Respiratory rate ≥ 30 breaths/min20Systolic blood pressure < 90 mmHg20Temperature < 35°C (95°F) or > 39.9°C (103.8°F)15Pleural effusion on x-ray10pH < 7.3530BUN ≥ 30 mg/dL or ≥ 11 mmol/L20Sodium < 130 mmol/L20Glucose ≥ 250 mg/dL or ≥ 14 mmol/L10Hematocrit < 30%10Partial pressure of oxygen < 60 mmHg or < 8 kPa⁷10 ¹Defined as any cancer (except basal- or squamous-cell cancer of the skin) that was active at the time of presentation or diagnosed within one year of presentation.²Defined as a clinical or histologic diagnosis of cirrhosis or another form of chronic liver disease, such as chronic active hepatitis.³Defined as a clinical diagnosis of stroke or transient ischemic attack or stroke documented by MRI or CT.⁴Defined as a history of chronic renal disease or abnormal blood urea nitrogen and creatinine concentrations documented in the medical record.⁵Defined as a clinical or histologic diagnosis of cirrhosis or another form of chronic liver disease, such as chronic active hepatitis.⁶Defined as disorientation with respect to person, place, or time that is not known to be chronic, stupor, or coma.⁷In the Pneumonia PORT cohort study, an oxygen saturation of < 90% on pulse oximetry or intubation before admission was also considered abnormal. Scoring & Recommendations The following 11 criteria or risk factors are presented first:Age Neoplastic diseaseCHF historyCerebrovascular historyRenal disease historyLiver disease historyAltered mental statusPulse ≥ 125 beats/minRespiratory rate ≥ 30 breaths/minSystolic blood pressure < 90 mmHgTemperature < 35°C (95°F) or > 39.9°C (103.8°F) If age is < 51 and the following 10 criteria are "no," then the remaining risk criteria will not be asked, no score is calculated, and the patient is assigned class I which is consistent with the original PORT design study by Fine et al (1997). RecommendationCriteriaPointsClass I: Outpatient care with oral antibioticsLow Risk: 0.1% mortality riskAge < 51No neoplastic diseaseNo CHF historyNo cerebrovascular historyNo renal disease historyNo liver disease historyNo altered mental statusNo pulse ≥ 125 beats/minNo Respiratory rate ≥ 30 breaths/minNo Systolic blood pressure < 90 mmHgNo Temperature < 35°C (95°F) or > 39.9°C (103.8°F)No points Class II: Outpatient care with oral antibiotics Low Risk: 0.6-0.9% mortalityDoes not meet Class I criteriaScore ≤ 70≤ 70Class III: Outpatient or inpatient admission Low Risk: 0.9-2.8% mortalityDoes not meet Class I criteriaScore 71-9071-90Class IV: Inpatient admission Moderate Risk: 8.2-9.3% mortalityDoes not meet Class I criteriaScore 91-13091-130Class V: Inpatient admission High Risk: 27.0-29.2% mortalityDoes not meet Class I criteriaScore > 130> 130 ConsiderationsAccording to the American Thoracic Society (ATS) and the Infectious Diseases Society of America (IDSA) practice guidelines on patients with community acquired pneumonia (CAP)(Armstrong, 2020; Womack & Kropa, 2022):Clinical judgement is a key component to determine the need for hospitalization.Low risk patients may have important contraindications to outpatient care, such as intractable vomiting, intravenous drug use, alcoholic use disorder, unreliable self care or severe psychiatric conditions that may require hospitalization to ensure compliance with treatment.Validated clinical prediction rules, like the CURB-65 and Pneumonia Severity Index (PSI), do not effectively determine the level of care required.The ATS/IDSA criteria for severe CAP is preferred to predict ICU admission.¹Five-day antibiotic treatment courses are recommended for all patients with CAP, with reassessment following treatment.For outpatients without comorbidities, treatment with amoxicillin, doxycycline or macrolide is recommended.Routine treatment of CAP with macrolide monotherapy is no longer recommended unless local resistance is low (< 25%). In outpatients with comorbidities and inpatients with non-severe pneumonia, a combination of a beta-lactam or third-generation cephalosporin plus a macrolide, or monotherapy with a respiratory fluoroquinolone is recommended. Patients should be treated for methicillin-resistant Staphylococcus aureus or Pseudomonas infection only if they present with risk factors for those pathogens.Consider the presence of sepsis. ¹Statement on COVID-19 (Armstrong, 2020): "Editor's Note: This ATS/IDSA guideline was produced before the COVID-19 pandemic, which has altered the diagnosis and management of lower respiratory tract infections. The current version of this guideline limits testing and antiviral treatment in patients with influenza, and we expect testing for and treatment of severe acute respiratory syndrome coronavirus 2 infection to become a long-standing element of standard pneumonia care. Although the IDSA has published initial guidelines for management of COVID-19, the situation is evolving rapidly (https://www.idsociety.org/practice-guideline/covid-19-guideline-treatment-and-management). Free information on COVID-19 is available from American Family Physician at https://www.aafp.org/journals/afp/explore/COVID-19.html and Essential Evidence Plus at http://www.essentialevidenceplus.com/content/eee/904.".