UNDERSTANDING PNEUMONIA

A SIMPLE GUIDE FOR YOU!

'PNEUMONIA' MAY SOUND LIKE A SCARY DIAGNOSIS BUT UNDERSTANDING IT IS THE FIRST STEP TOWARD BEATING IT!!

WHAT IS PNEUMONIA ?

PNEUMONIA is an infection of lungs in which the air containing sacs (alveoli) are filled with fluid or pus. Because of the alveolar filling, exchange of O2 and CO through blood capillaries in the alveoli will be affected resulting in poor oxygenation. All though recovery is common in majority with proper management, it can have serious complications and even death, especially in very young children and old adults.

PNEUMONIA is classified into 3 types.

COMMUNITY ACQUIRED PNEUMONIA (CAP) : Infection is acquired outside healthcare settings, ie. in the community. Most common causes are:

Streptococcus Pneumoniae, H.Influenza, Staphylococcus Aureus etc. and Atypical pathogens like Mycoplasma, Legionella and Viruses ( Influenza etc.) .

HOSPITAL ACQUIRED PNEUMONIA (HAP) : Pneumonia occuring 48 hours or more after hospital admission. VENTILATOR ASSOCIATED PNEUMONIA (VAP) is a subset of HAP, occurs after intubation and mechanical ventilation.

HEALTHCARE ASSOCIATED PNEUMONIA( HCAP) : Occurs in patients with recent healthcare exposure outside the hospital ( nursing homes and dialysis centers)

INHALATION ROUTE OF BACTERIA AND VIRUSES

WHAT CAUSES COMMUNITY ACQUIRED PNEUMONIA ?

Infection is mostly caused by bacteria like Streptococcus Pneumonia, H.Influenza, Klebsiella pneumoniae (in alchoholics),Staphylococcus Aureus (recent influenza infection). These are called TYPICAL pneumonias because of sudden onset associated with moderate to severe symptoms. Pneumonia is called ATYPICAL , if it has a slow onset and mild to moderate symptoms and is caused by Mycoplasma, Legionella, Viruses like Influenza and Covid 19. Rarely pneumonias may be caused by fungi.

WHAT ARE THE RISK FACTORS ASSOCIATED WITH PNEUMONIA ?

Cigarette smoking

Alcoholism

Aspiration (when the oral contents like food ,fluids and vomit are inhaled accidentally into lungs.)

Very young children less than 5 years and older people aged more than 65 years.

COPD, Heart disease, Diabetes mellitus

Usage of Oral steriods, immunosupressent drugs.

Recent Hospitalization.

WHAT ARE THE SYMPTOMS FOR WHICH A PATIENT WITH PNEUMONIA VISITS A PULMONOLOGIST?

Cough is the main symptom along with green/yellow/rusty/blood tinged sputum.

Sudden onset of fever with chills and rigors.

Difficulty in breathing, rapid breathing

Chest pain especially during cough or deep breathing.

Fatigue, body aches.

In ELDERLY PEOPLE symptoms may be different, like confusion, low alertness, altered consousiouness and absence of fever.

SYMPTOMS IN A PATIENT WITH PNEUMONIA

HOW IS PNEUMONIA DIAGNOSED?

EVALUATION BY A PULMONOLOGIST

The pulmonologist evaluates patient's history details,conducts physical examination and will investigate further with:

XRAY CHEST OF DIFFERENT PATIENTS SHOWING PNEUMONIA

1. Chest X ray (opacities in the lung suggest pneumonia)

2. Blood tests: Complete blood count( CBC), White cell count(WBC or TLC) ,when raised indicate infection. A white cell count more than 15000/ mic L. or less than 4000/ mic.L. indicates severe infection

3. Sputum tests: Sputum Gm staining, Culture and Sensitivity and Blood cultures before receiving antibiotics, in order to identify the causative organism.

4. Checking O2 levels in the blood by pulse oxymetry. When Spo2 is less than 92% or ABG report shows PaO2/FIO2 < 250 , patient requires admission for O2 supplementation.

5. In serious cases Lver Function Tests (LFT) and Renal function tests (RFT) may be deranged.

6. Raised CRP (C Reactive Protein) levels indicate pneumonia and raised Procalcitonin (PCT) levels suggest bacterial pneumonia.

7. In more complex cases CT scan, Ultra sound and FOB might be necessary.

8. Pneumococcal/Legionella Urinary Antigen tests: in moderate to severe pneumonias.

9. Polymerase Chain Reaction (PCR) testing of sputum, BAL, throat swab : Mutiplex PCR has emerged as an important diagnostic tool to know the pathogen particularly with regard to Respiratory viruses and fastidious organisams like Legionella and Mycoplasma.

SPUTUM GRAM'S STAIN SHOWING PNEUMOCOCCI

COMPLICATIONS OF PNEUMONIA:

Pleural effusion,Empyema, Lung abscess, Sepsis, Septic shock, Respiratory failure/ ARDS.

Severe pneumonia may precipitate cardiovascular complications like acute MI (Myocardial Infarction), congestive heart failure, multiorgan failure.

Viral pneumonias like COVID 19 pneumonia may be complicated by myocarditis.

COMPLICATIONS OF PNEUMONIA SHOWING LUNG ABSCESS AND PLEURAL AFFUSION

HOW IS A PNEUMONIA MANAGED BY A PULMONOLOGIST OR A CHEST PHYSICIAN?

At the outset the pulmonologist,after preliminary examination and investigations, assesses the severity of the pneumonia using PSI /PORT score

( Pneumonia Severity Score using 20 variables and Patient Outcomes Reach Team) and decides Level Of Care, whether the patient can be treated as an OP (Out patient) or an IP (In Patient) requiring hospital admission or ICU care.

For eg, if PSI/PORT score is 1 &2 class, ( low risk, < 70 points) patient is often treated as Out patient.

EMPIRICAL ANTIBIOTIC THERAPY IS THE MAINSTAY OF TREATMENT OF PNEUMONIA.

EMPIRIC ANTIBIOTIC TREATMENT IS STARTED PROMPTLY. It includes coverage of typical and atypical bacteria with Amoxycillin and/ Macrolide such as azithromycin or clarithromycin /doxycyclin.

During Influenza season it is reasonable to initiate Oseltamivir /Zanamivir/Peramivir

For a patient with pneumonia but has comorbidities like chronic lung disease, heart disease,renal failure, diabetes mellitus, the antibiotic combination will consist of Betalactum antibiotic,like Amoxycillin+ Clavulanic acid or cefpodoxim or cefuroxime and a macrolide or doxycyclin.

Hospitalised patients and ICU patients require more aggressive tratment with Betalactum antibiotics and Respiratory Fluoroquinolone ( like moxifloxacin , levofloxacin.)

Special concerns:

If Peudomonas aeruginosa is considered, anti pseudomonal and anti pneumococcal betalactum is indicated like piperacillin-tazobactum,cefepime,imipenem/meropenem.

If MRSA or Methicillin Resistant Staphylococcus Aureus is considered, vancomycin/ linezolid is added.

NEWER antibiotics approved by FDA are:

Omadacyclin, lefamulin,solithromycin,delafloxacin and ceftobiprole.

In SEVERE PNEUMONIA cases, additional supportive and critical treatment are required.

For pneumonia with hypoxia( low O2 levels):

Supplementary oxygen with nasal cannula or facemask is required.

For pneuomonia wirh respiratory failure or ARDS ( Acute Respiratory Distress Syndrome) :

NIV( Non Invasive Ventilation) or IV ( Invasive ventilation with intubation and mechanical ventilation) are needed to meet the ventilatory needs because of increased work of breathing.

For pneumonia with sepsis /septic shock:

Aggressive fluid resuscitation with IV crystalloids and vasopressors.

WHAT IS THE DURATION OF ANTIBIOTIC TREATMENT?

For mild to moderate pneumonia, antibiotic therapy is given for 3 days.

For delayed clinical stability , given for 5 days

For severe pneumonia ( ICU) or pneumonia with complications treatment is given for 7 days/ individualised as per the needs.

VARIOUS SCORING SYSTEMS in use to assess the severity of pneumonia and to determine the need for hospital admission are :

1.PSI/PORT SCORE

2.CURB 65 or CRB 65 (Confusion,Urea>7mmol/L or 19 mg/dl,Respiratory rate>30/mt,Blood pressure:systolic<90 or diastolic<60 mm Hg and age> 65)

3. SMART COP SCORE

4.CURXO SCORE

5.IDSA/ATS MINOR & MAJOR CRITERIA

MORTALITY RATE IN PNEUMONIA:

The overall 30 day mortality rate ( death rate) in pneumonias is 15.7%, mostly in hospitalised, severe pneumonia cases.

WITH THE RIGHT AWARENESS, EARLY GUIDANCE AND CARE BY YOUR PULMONOLOGIST, PNEUMONIA IS NOT JUST TREATABLE - IT' BEATABLE!