Pneumonia and Pleural effusions Flashcards
Pneumonia:
Inflammation of the lungs with consolidation or interstitial lung infiltrates
Most often categorized according to the causative organism
6th leading cause of death in US:
pneumonia
most common S/S of PNA:
Cough Fever Pleuritic chest pain Dyspnea Sputum production Rales/crackles on lung exam Increased tactile fremitus if consolidation Decreased tactile fremitus if effusion
Causative organisms bacterial, viral, fungal
Bacterial PNA:
-mucopurulent sputum
Viral or atypical organism PNA:
scant or watery sputum
PNA most common diagnostic tools:
-often have leukocytosis with left shift
-History and clinical Exam
CXR
Pulse oximetry
Routine lab testing – CBC, BMP, LFTs
Sputum gram stain and culture
Blood culture
ABG (arterial blood gas)
Thoracentesis if pleural effusion present
Most basic PNA workups:
Clinical exam
CXR
(Pulse oximetry)
PNA workup:
Patient stable, looks toxic, fever, dyspnea:
Start empiric antibiotic treatment
Obtain labs
Blood culture
Obtain a sputum sample, stain and culture
May add an ABG (hospital setting)
Thoracentesis if effusion found on CXR, ideally in an inpatient setting
Tx of PNA
- bacterial: antibiotics
- Viral: supportive/anti-virals
- Fungal: anti-fungals
- Pleural effusion: thoracentesis
types of PNA
Community acquired pneumonia Hospital acquired pneumonia Ventilator associated Aspiration pneumonia Mycoplasma/atypical Fungal PCP
CAP definition:
an acute infection of the pulmonary parenchyma in a patient who has acquired the infection in the community, as distinguished from hospital-acquired (nosocomial) pneumonia.
most common cause of CAP:
Streptococcus pneumoniae is the most common cause of community-acquired bacterial pneumonia worldwide
CAP general info:
The overall rate of community-acquired pneumonia (CAP) in adults is approximately 5.16 to 6.11 cases per 1000 persons per year; the rate of CAP increases with increasing age
There is seasonal variation, with more cases occurring during the winter months
The rates of pneumonia:
Men>Women
African American > Caucasians
Determining whether to tx at home or admit use what score:
CURB-65
typical bacterial CAP pathogens:
Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis
3 pathogens account for approximately 85% of CAP cases.
antibiotic choice of CAP:
Outpatient typically treated for 7-10 days of oral antibiotics with close follow up Culture results?
Most patients with CAP who are admitted to the hospital are treated with intravenous medications initially and then complete a 12-day oral course of therapy for a total of 14 days of combined intravenous and oral therapy.
when to use Pneumovax:
Two types of pneumococcal vaccine one that covers 23 serotypes and a new one covering an additional 13 serotypes
All patients ≥65 years: ACIP recommends routine vaccination with both PPSV23 (23-valent pneumococcal polysaccharide vaccine) and PCV13 (13-valent pneumococcal conjugate vaccine)
For those whom an additional dose of PPSV23 is indicated, this subsequent PPSV23 dose should be given 6-12 months after PCV13 and ≥5 yr after the most recent dose of PPSV23
HAP
Hospital-acquired (or nosocomial) pneumonia (HAP) is pneumonia that occurs 48 hours or more after admission and did not appear to be incubating at the time of admission.
VAP
Ventilator-associated pneumonia (VAP) is a type of HAP that develops more than 48 to 72 hours after endotracheal intubation.
HCAP
Healthcare-associated pneumonia (HCAP) is defined as pneumonia that occurs in a non-hospitalized patient with extensive healthcare contact, as defined by one or more of the following:
- Intravenous therapy, wound care, or intravenous chemotherapy within the prior 30 days
- Residence in a nursing home or other long-term care facility
- Hospitalization in an acute care hospital for two or more days within the prior 90 days
- Attendance at a hospital or hemodialysis clinic within the prior 30 days
QUESTION: Why is it so important to do a good history and find out if a patient has one of these types of pneumonias versus community acquired pneumonia?
Multi-drug resistance!!!
For example, the definition of multidrug resistance in gram-negative bacilli, which are an important cause of HAP, VAP, and HCAP, is variably defined as resistance to at least two, three, four, or eight of the antibiotics typically used to treat infections with these organisms
Extensively drug-resistant (XDR) gram-negative bacilli are defined by resistance to all commonly used systemic antibiotics except colistin, tigecycline, and aminoglycosides.
Awareness of local resistance patterns is critical for decisions regarding empiric therapy for HAP, VAP, and HCAP.
HAP epidemiology:
Most cases that are diagnosed within 5 days of admission are due to sensitive bacteria, unless the patient was exposed to antibiotics within the last 90 days.
Patients with HAP diagnosed after 5 days typically have pneumonia due to a resistant bacteria.
The crude mortality for HAP may be as high as 30% to 70%, but many patients die of their underlying disease rather than HAP itself.
Attributable mortality is about 10%. (due to PNA bug itself)
HAP is caused most by what?
Bacteria cause most cases of HAP and ventilator-associated pneumonia (VAP)
Most are due to aerobic gram-negative bacilli such as Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, and Acinetobacter species
In addition to methicillin-sensitive Staphylococcus aureus (MSSA), both hospital-acquired and community-acquired strains of MRSA are causing an increasing number of HAP cases.
most common aerobic gram - bacilli that causes HAP:
Psuedomonas aeruginosa
HAP Dx testing:
Culture the bug!!!! CXR CT Blood culture CBC, Chem, LFTs Bronchoalveolar lavage
Early onset HAP, VAP, HCAP Tx:
Early onset (< 5d since admission) and no MDR risk factors: Ceftriaxone 2 g IV or IM q24h or Levofloxacin 750 mg IV or PO q24h or Ampicillin-sulbactam 3 g IV or IM q6h or Ertapenem 1 g IV or IM q24h Duration of therapy: 8d
Late onset HAP, VAP, HCAP Tx:
Late onset (≥ 5d since admission), MDR risk factors present, or diagnosis of HCAP: Cefepime 2 g IV q8h or Ceftazidime 2 g IV q8h or Imipenem-cilastatin 500 mg IV q6h or 1 g IV q8h or Meropenem 1 g IV q8h or Piperacillin-tazobactam 4.5 g IV q8hPLUS Vancomycin 15 mg/kg IV q12h[5, 6] or Linezolid 600 mg IV q12h[5] PLUS Ciprofloxacin 400 mg IV q8h or Levofloxacin 750 mg IV q24h
Duration of HAP, VAP, HCAP tx therapy:
If clinical improvement is noted in 48-72h and cultures are negative, consider stopping antibiotics
If clinical improvement is noted in 48-72h and cultures are positive, adjust regimen per susceptibilities and continue antibiotics for 7-8d
If there is no clinical improvement and cultures are negative, look for alternative diagnoses
If there is no clinical improvement and cultures are positive, adjust regimen per susceptibilities
Highlights of aspiration PNA
Pneumonia caused by the aspiration of oropharygneal or gastric contents
Diagnosis is based on clinical signs or symptoms of pneumonia in a person with a history or risk factors for aspiration.
Sputum or tracheal Gram stain reveals mixed flora.
Infection usually involves the dependent lung lobe.
Complications of disease include lung abscess and empyema.
Very common in hospitalized patients, patients on a vent, patient with swallowing disorders/post-stroke or some other neurological condition
Epidemiology of aspiration PNA:
Aspiration can occur regardless of sex, age group, or ethnicity
True incidence of aspiration pneumonia is difficult to assess because many cases of community-acquired pneumonia (CAP) or hospital-acquired pneumonia are likely the result of aspiration that was undiagnosed
Some studies suggest that aspiration pneumonia may be the cause of as many as 5% to 15% of CAP cases
It occurs most commonly in older hospitalized or nursing-home patients
It is the most common cause of death among patients with swallowing dysfunction related to neurologic disease
Aspiration PNA presentation and workup:
History and PE, history is KEY!!!
Poor dentition, advanced age, swallowing dysfunction, and presence of a feeding tube
Symptoms include cough, dyspnea, and pleuritic chest pain, but may be nonspecific and be present for a week or more after the event
Signs such as fever, rales, tachypnea, and frothy or purulent sputum should raise the suspicion for aspiration pneumonia.
At minimum, CXR, SPO2, CBC
Consider sputum culture/gram stain, not usually blood culture since usually clear and being treated before advances to bacteremia; ABG in hospital
Aspiration PNA Tx:
Empiric treatment requires coverage for anaerobic organisms
Treatment always tailored to culture and sensitivities if available/useful
Otherwise, empirical antibiotics started as soon as aspiration PNA is diagnosed
In the presence of infection, antibiotics should be continued for at least 7 to 10 days in a patient who responds promptly and for a minimum of 2 weeks if highly resistant pathogens such as Pseudomonas aeruginosa are isolated
Antibiotic choices are slightly different based on where/who you are treating
CA aspiration PNA:
clindamycin : 300 mg orally every 6 hour; or 600 mg intravenously every 8 hours
levofloxacin : 750 mg orally or intravenously once daily
moxifloxacin : 400 mg orally or intravenously once daily
piperacillin/tazobactam : 3.375 g intravenously every 6 hours ampicillin/sulbactam : 1-2 g intravenously every 6 hours imipenem/cilastatin : 250-500 mg intravenously every 6 hours
HA or “toxic” aspiration PNA Tx:
cefepime : 1-2 g intravenously every 12 hours or
ampicillin/sulbactam : 1-2 g intravenously every 6 hours or
piperacillin/tazobactam : 4.5 g intravenously every 6 hours
OR
imipenem/cilastatin : consult specialist for guidance on dose or
meropenem : consult specialist for guidance on dose
– AND –
tobramycin : consult specialist for guidance on dose or
gentamicin : consult specialist for guidance on dose
– AND –
linezolid : 600 mg intravenously every 12 hours or
vancomycin : 15 mg/kg intravenously every 12 hours initially, adjust based on vancomycin levels
Atypical/ mycoplasma pan is mostly caused by:
Mycoplasma pneumoniae, Chlamydophila pneumoniae, or Legionella pneumophila.
Atypical PNA highlights:
Community-acquired and often seen in young adults living in close proximity.
Atypical bacterial pneumonia is most commonly caused by Mycoplasma pneumoniae, Chlamydophila pneumoniae, or Legionella pneumophila.
Usually presents with a low-grade fever, persistent dry cough, and constitutional symptoms, for example, malaise.
Treatment is often outpatient based with a macrolide or doxycycline.
Extrapulmonary manifestations may occur, especially in Mycoplasma pneumoniae infections.
Why is Atypical PNA atypical?
Atypical bacterial pneumonia is caused by atypical organisms that are not detectable on Gram stain and cannot be cultured using standard methods.
The most common organisms are Mycoplasma pneumoniae, Chlamydophila pneumoniae, and Legionella pneumophila.
Atypical bacterial pneumonia generally is characterized by a symptom complex that includes headache, low-grade fever, cough and malaise.
Constitutional symptoms often predominate over respiratory findings smouldering illness
Smoldering illness:
exists in a suppressed or concealed state (S/Sx) not as prominent compared to typical PNA
atypical PNA epi:
Mycoplasma pneumoniae causes up to 15% of cases of community-acquired pneumonia
Infection is common in children and young adults, and is often seen in close community settings such as boarding schools, colleges and military bases
Legionella pneumophila is responsible for a low percentage of community-acquired pneumonia cases, but it is responsible for up to 16% of cases that require hospitalization.
atypical prevention /workup:
History and PE
normal WBC
Dry cough, that has lasted for a while/not resolving, constitutional symptoms like headache, malaise, with or without overt respiratory symptoms, age <50
A vesicular rash may accompany Mycoplasma
Diarrhea may accompany Legionella infection
CXR, labs like CBC, CMP, sputum culture, usually not toxic appearing enough to warrant a blood culture
The CXR usually confirms infiltrates and may show more extensive abnormalities than PE suggests
A low oxygen saturation indicates a more severe course of disease requiring hospitalization.
atypical Tx:
Treatment:
Usually treatment is based on clinical diagnosis alone
Atypical bacterial pneumonia pathogens generally do not respond to beta-lactam antibiotics and require treatment with a macrolide, tetracycline, or fluoroquinolone
First-line choices:
Macrolide azithromycin 500 mg orally once daily on the first day, followed by 250 mg once daily for 4 days OR clarithromycin 500 mg orally (immediate-release) twice daily for 14-21 days
Doxycycline100 mg orally twice daily for 14 days
common fungi that cause fungal pna
Histoplasma capsulatum, Blastomyces dermatitidis, Coccidioides immitis.
typical fungal pna s/s
Flu like sx’s: Fever, occasional chills, myalgia, cough, dyspnea, chest pain.
fungal pna highlights:
Uncommon in immunocompetent patients.
Concern in neutropenic patients, organ recipients, chronic steroid use, or other immunocompromised states.
Fungal pneumonia common pathogens include Histoplasma capsulatum, Blastomyces dermatitidis, Coccidioides immitis.
Certain fungi are endemic to certain geographic regions of North America and found in soils contaminated bird/bat droppings, caves, decayed buildings (spores inhaled).
Causes typical respiratory infection symptoms and signs, note it can also spread hematogenously and become disseminated.
Diagnosis is suspected based on clinical and epidemiologic characteristics and confirmed by CXR, culture or specific serum antigen testing.
Treatment is antifungals.
Consultation with Infectious Disease is highly recommended.
PCP pneumonia highlights::
The organism was known formerly as Pneumocystis carinii (pneumonia, thus PCP), this what defines this infection
Still the most common AIDS-defining opportunistic infection, usually happens with CD4 counts < 200 cells/ul
Suspicion for Pneumocystis pneumonia (PCP) is based on clinical signs or symptoms of pneumonia in a person with immune suppression, especially when due to HIV infection
Diagnosis is made by detection of the organism in either induced sputum or bronchoalveolar lavage (BAL)
The treatment of choice is trimethoprim/sulfamethoxazole (TMP/SMX).
PCP pneumonia epi:
Pneumocystis pneumonia (PCP) is the most common AIDS-defining illness in the US in children, adolescents, and adults
In HIV-positive adults, the greatest risk factor for developing PCP is a CD4 cell count of <200 cells/microliter, with risk increasing the lower the CD4 cell count falls below this level
In HIV-negative patients, the overall incidence of PCP is low and occurs almost exclusively in patients who have other causes of immunocompromise
PCP etiology/pathophys:
Pneumocystis pneumonia (PCP) is caused by the fungal organism Pneumocystis jirovecii
Infection in the lung starts with the multiplication of the organism in the alveoli
As infection progresses, alveoli fill with exudates, there is type 2 pneumocyte hyperplasia, and mononuclear cells infiltrate the lung
Desquamation of the alveolar lining cells creates increased permeability of the alveolar capillary membrane and noncardiogenic pulmonary edema.
PCP PNA presentation/workup
History and PE, history is KEY!!!
Clinicians should suspect PCP when caring for adult or adolescent patients who are HIV-positive
Especially if they are non-adherent with highly active antiretroviral therapy (HAART) or PCP prophylaxis, have had a previous episode of PCP, and/or have a CD4 cell count of <200 cells/microliter.
If NOT HIV positive/AIDs, then have they undergone: bone marrow transplant, solid-organ transplant, a hematologic malignancy or are they under chronic use of corticosteroids ± other immunosuppressive drugs?
In HIV-positive PCP, presentation is often an insidious progression of fatigue, fevers, chills, sweats, nonproductive cough, and dyspnea over several weeks atypical presentation
PCP PNA presentation/workup cont:
In HIV-negative patients, the presentation is typically more rapid and more severe.
The findings on physical examination are often nonspecific and include the usual fever, tachypnea, and tachycardia
But sometimes pulmonary examination is often normal but occasionally demonstrates mild crackles on auscultation
Other symptoms may include weight loss & oral candidiasis
CXR, LDH (elevated in 90% of HIV patient with active PCP), induced sputum and arterial blood gas (graded as mild or severe depending on results)
Consider bronchoalveolar lavage to get a high quality sputum sample, PFTs and CT of the chest depending on length of course and severity of presentation
PCP tx:
When PCP is suspected, treatment should be initiated immediately even prior to specific diagnosis
Treatment duration for PCP is 21 days in HIV-positive patients, 14 to 21 days in all other patients
Mild-to-moderate PCP (defined as having both a room air pO2 70 mmHg or greater and an A-a gradient of 35 mmHg or less)
-Trimethoprim/sulfamethoxazole (TMP/SMX), given either intravenously or orally 15-20 mg/kg/day.
Moderate-to-severe PCP (defined by either a room air pO2 <70 mmHg or an A-a gradient of >35 mmHg)
-Admitted to hospital for intravenous TMP/SMX 15-20 mg/kg/day IV) combined with a corticosteroid (prednisone or methylprednisone)
Prophylaxis trimethoprim/sulfamethoxazole : 80/400 mg to 160/800 mg orally once daily
Pleural effusions:
Accumulation of fluid in pleural cavity between lung and thoracic wall
Etiology (Types):
Transudate
Exudate
Empyema- infection
Hemorrhagic/Hemothorax -blood (trauma)
Neoplastic
Chylous- disruption of thoracic duct
most common pleural effusion:
Transudative: (Most common)
Caused by increase in pulmonary venous pressure or hypoproteinemia
Clear, yellow/straw colored
Etiologies:
CHF
Cirrhosis
Nephrotic Syndrome
Exudative pleural effusion:
Caused by inflammation Higher concentration of protein Deep color, turbid Etiologies: Infection: Empyema, TB, Parapneumonic Neoplastic: Lung CA, Metastatic disease Trauma: Hemothorax, Chylothorax
pleural effusion presentation/ workup
Common Symptoms: dyspnea, pleuritic chest pain, dry cough; +/- Fever/Chills Common Signs: Diminished breath sounds, dullness to percussion, decreased tactile fremitus Diagnostic Tests: Basic Labs (CBC, BMP) CXR CT Scan Thoracentesis U/S guided vs Bedside Pleural Fluid Analysis Cell Count/Cytology Protein, LDH, Glucose Gram stain, Fungi, AFB Cholesterol, Triglycerides
pleural effusion tx:
Ultimately Goal is treat the underlying cause
Thoracentesis
Pleurodesis (Chronic Effusions)
Serial CXR
