Pneumonia (FL Autonomous Practice INITIAL Pharmacology)

Pneumonia has been deadly throughout history, with writings dating back to the early Chinese and Greeks. In the late 1800s and early 1900s, pneumonia was the primary cause of infectious deaths (Chow, 2022). Independently, French microbiologist Louis Pasteur and American physician George Sternberg identified and published the primary bacterial cause of this condition, Streptococcus pneumoniae, in 1881.

Additional studies in the early 1900s revealed how this elongated, gram stain-positive bacteria's physical structure interacted pathologically with our immune system. It was found that the cell wall of Streptococcus pneumoniae possesses a thick wall known as a capsule. The thick wall contains a thick layer of polysaccharides which caused increased resistance to any treatments available at that time. The thick wall limits how our immune system fights the bacteria, requiring an active supply of immune antibodies to combat and destroy the infection (Chow, 2022). 

Sulphapyridine, the first of our current families of antibacterial medications introduced in the 1930s, gained quick popularity and acceptance following its successful use in treating Winston Churchill's bacterial pneumonia during the heat of World War II (Chow, 2022). Penicillin, a newcomer in the early 1940s, rapidly replaced sulfa medications to treat pneumonia. As a point of interest, medical historians link the eager readiness with which practitioners throw new antibiotics into the fight against the ancient advisory pneumonia with our current plight of infections becoming antibiotic-resistant (Shevardnadze, 2021).

The first pneumonia vaccine arrived in 1977 and was called the pneumococcal polysaccharide vaccine (PPV). Unfortunately, the number of Streptococcal serotypes, i.e., subtypes, that it treats was limited. Around 2000, a second vaccine called the pneumococcal conjugate vaccine (PCV) hit the market covering more Streptococcal strains, including some antibiotic-resistant ones.

Sadly, some new universal pneumococcal vaccines (UPVs) not approved in the United States yet currently fielded around the world have been observed by researchers to increase antibiotic resistance among the bacteria they are intended to suppress. Nevertheless, the World Health Organization (WHO) pushes forward with immunization campaigns to meet their Sustainable Development Goal target (SDG 3.2.1) of reducing child mortality from pneumonia-related death (WHO, 2021).

Pneumon, meaning "lung," and pneumonic, "affecting the lungs," are the Greek word origins for pneumonia or "lung disease" (Wordnik, 2022). Details have been recorded about this "choking" condition since the times of Homer and the great philosophers.

Recognizing that the specific causative organism or contaminant may lead to slight variation, here are the tell tales of pneumonia.

In addition to the list of common symptoms above, viral pneumonia often shows as:

• A dry cough.
• Headache and generalized muscle pains.

Symptoms include:

• Fever and chills.
• Bluish tinge to lips and skin.
• Grunting breaths.
• Inward pull of muscles between ribs when breathing.
• Rapid breathing.
• Visible widening of nostrils with each breath (National Heart, Lung, and Blood Institute, 2022).

Bronchopneumonia is a type of pneumonia that primarily affects the bronchi and bronchioles, the system of tubes that bring air into your lungs.

Bronchitis is a relatively mild yet annoying inflammatory swelling of the large airways of the respiratory system. It may be chronic or acute and usually involves an upper respiratory virus or other irritants, producing inflammation, mucous, and coughing. Normal vital signs and oxygen saturation readings are usually sufficient for ruling out bronchitis from bronchopneumonia (Singh et al., 2022). Be aware that chronic bronchitis increases the potential for developing pneumonia (Villines, 2020).

Figure 2: Anatomy of the Lung

Conversely, bronchopneumonia tends to be more severe in presentation than its milder cousin, bronchitis. With the presentation of the pneumonia symptoms mentioned earlier, look for fever, diminished oxygenation levels, and characteristic patches or shading visible around the bronchioles on a chest x-ray (CXR) or other scans (Jain et al., 2022). These points of thickening tend to be pockets of suppurative (filled with pus) inflammation that, while positioned proximal to the bronchi, may or may not be in a single lobe. Occasionally these points form into lung abscesses or areas of pus filled with the breakdown of the lung tissue. When well established, these pockets of pus and infection may spread to the pleural space around the lungs or lobes of a lung. Fibrinopurulent exudate then fills this space, a condition known as empyema (Molineux, 2022).

Bacterial pneumonia centering on the large airways often spreads to other parts of the lungs if not recognized early and treated effectively.

Figure 3: Bronchopneumonia

Lobar pneumonia is another grouping of pneumonia that refers to infections or inflammations causing regional congestion affecting an entire section, or lobe, of a lung. The term consolidation, which refers to the filling of open airspaces in the lungs with fluids, is often interchanged with the correct grouping terminology (British Medical Journal, 2022).

There are four distinct stages of lobar pneumonia.

Client visualization, observation, and interactions with the care provider are, and always will be, the most important priority when dealing with respiratory issues (National Heart, Lung, and Blood Institute, 2022; Buchan et al., 2021).

• Ask about symptoms experienced and the period in which they began.
• Inquire about the possibility of exposure to others with breathing problems.
• Inquire if exposed to environmental or industrial irritants that made breathing difficult.
• Discuss medications, both prescription and over-the-counter, taken now and at the start of breathing issues.
• Discuss changes in past or current medical conditions.
• Ask about recent travel.
• Inquire about smoking or exposure to airborne irritants (including vape smoke).
• Discuss recent exposure to birds or other animals.

• Swab tests. Swabs of the throat, nose, and that hard-to-reach area at the back of the nose.
  • Influenza swab.
  • SARS-CoV-2 (Covid) swab.
  • Pneumonia Plus Panel (or other Multiplex Panels) – looks for DNA for twenty-seven different bacteria and viruses.
• Blood tests.
  • Complete blood count (CBC) with differential – to determine how well the immune system fights the infection.
  • Basic Metabolic Panel (BMP) – assessing kidney function, electrolytes, and blood sugars.
  • Blood Gas – arterial blood showing oxygenation, pH, and carbon dioxide levels to determine how functional the lungs truly are.
  • Blood Culture – the best vehicle to trap, identify, and find the best antibiotic for serious infections.
  • Polymerase Chain Reaction test (PCR) – looking for DNA clues.
  • Beta-D-glucan test - beta-D-glucan is part of the cell walls of fungi, so when a fungal infection is suspected of causing the pneumonia, this is a great time saver, bypassing the time it takes to grow a sputum fungal smear.
  • C-reactive protein (CRP) – looks at inflammation levels because pneumonia is, to a great extent, all about inflammation.
• Sputum tests: to identify what infection or irritant the lungs are fighting to expel.
  • Sputum Culture, Gram stain, Fungal smear, PCR, and of course, a direct fluorescent antibody (DFA) where, when observed using a special microscope, the sample will glow in the presence of certain infections.
• Urine tests.
  • Two bacteria that can cause pneumonia, Streptococcus pneumoniae and Legionella pneumophila, can be revealed by urine analysis (Testing.com, 2021).
• Pleural fluid tests.
  • Thoracentesis may not be a do-this-first procedure for pneumonia. Yet when extra pleural fluid, or empyema, is visualized with a chest x-ray or CT scan, it may be time to needle that cavity and determine what is there.

• Physical examination: Lung sounds provide valuable information, so listen.
  • Rhonchi (low-pitched breath sound) occurs when air tries to pass through bronchial tubes that contain fluid or mucus.
  • Crackles (high-pitched breath sounds) occur if the small air sacs in the lungs fill with fluid and any ability for air movement remains in the sacs. The air sacs fill with fluid when a person has pneumonia or heart failure.
  • Wheezing (high-pitched whistling sound) caused by constriction or narrowing of airways.
  • Stridor (a harsh, vibratory sound) is caused by the narrowing of the upper airway.
• Vital signs with pulse oximetry: Initiate on arrival into care and continue according to care protocols. Pulse oximetry is essential for dealing with respiratory afflictions and can be very telling when looking at oxygen levels before, during, and after a coughing fit.
• CXR: Provides visualization of tissue congestion.
• Pulmonary Function Test (PFT): Measurement of amounts of air inhaled and exhaled.
• Chest ultrasound: Another helpful tool for visualizing affected tissue.
• Bronchoscopy: Allows a direct look at the inflammation of the airways while providing a means of sample collection for tissue and fluids.
• Chest CT scan: It shows much more detail than a traditional CXR and excels at finding abscesses, tissue tears, necrotizing areas, and empyema.

Community-acquired Pneumonia (CAP)- When pneumonia occurs in those who have not recently been in a hospital or care facility, it is called community-acquired pneumonia (CAP). Pneumonia manifesting within the first 48 hours of a hospital or care facility admission is also CAP, as the causative infection is considered to have already been present and "incubating" at the time of admission.

NOTE: Walking Pneumonia (WP) is technically not a medical term yet is commonly used in healthcare to refer to any pneumonia with mild symptoms. WP is now regarded to be a CAP.

Hospital-acquired Pneumonia (HAP) – Is also known as nosocomial pneumonia. HAP shows initial symptoms after the first 48 hours of entry into a hospital or care facility. The presumption is that it is an organism endemic to the health care facility causing the infection.

Ventilator-acquired Pneumonia (VAP) – A nosocomial infection of the lung tissue that develops 48 hours or longer after intubation for mechanical ventilation. Symptoms may develop following general surgery or other procedures requiring intubation.

Healthcare-associated Pneumonia (HCAP) - Is a term no longer used! You will still see and hear it, as it takes decades to fully change health vernacular. So, what HCAP refers to is pneumonia acquired in health care facilities (e.g., nursing homes, hemodialysis centers, urgent care waiting rooms) or manifests within three months of hospitalization (Miller, 2021).

Bacterial Pneumonia – pneumonia caused by a bacterial pathogen, most commonly (around 50% of bacterial pneumonia cases) by Streptococcus pneumoniae, which generally abides asymptomatically in the human upper respiratory tract. Bacterial pneumonia typically infects more than 900,000 Americans yearly who become symptomatic after an upper respiratory viral cold or flu. Other common bacteria causing bacterial pneumonia include Mycoplasma pneumoniae, Chlamydophila pneumoniae, Haemophilus influenzae (the bacteria), and Legionella pneumophila.

Viral Pneumonia – Is, of course, caused by a virus or viruses. Roughly one-third of all pneumonia cases are viral. Certain viruses are associated with causing pneumonia, mostly on an opportunistic basis. The more common ones include Respiratory syncytial virus (RSV), Influenza virus, Parainfluenza virus, Adenovirus, Measles virus, and Coronaviruses (of which there are several), including SARS-CoV-2, the virus that causes COVID-19.

Fungal Pneumonia – While more common outside the United States, fungal spores will attempt to grow wherever they find favorable conditions. In the southwestern U.S., the valley fever fungus, Coccidioides, is a frequent respiratory pathogen. Other common fungal pneumonias include Histoplasma capsulatum (histoplasmosis), Pneumocystis jirovecii (aka, Pneumocystis pneumonia, associated primarily with the immunocompromised), Blastomyces fungi, and Cryptococcus neoformans. Fungal pneumonia is a real threat to the immune-compromised. If your coughing client falls into that category, be sure fungal pathogens are investigated.

Chemical Pneumonia – Any chemical irritant can provoke pneumonia when it inflames the lungs. Remember, pneumonia is about inflammation, not just infection. Chemical weapons, gases, pool cleaning chemicals, and the volatiles used in air fresheners are examples of inhaled chemical irritants. Dr. Raymond Casciari, pulmonologist, offers a great rule of thumb for suspecting chemical pneumonia in a 2021 interview with Health magazine. "If your eyes are burning, your lungs are too."

Aspiration Pneumonia- Aspiration, or entry of unwanted substances into the lower airway passages and lungs, is one of the most common complications following general surgery. Also, 5 to 15% of all CAPs are traced back to aspiration, with 18% of retirement care clients experiencing aspiration-induced pneumonia at some point. Weakness or failure of the epiglottis, which closes the laryngeal inlet during swallowing protecting the airways, or an abnormal cough reflex are prime factors in aspiration. Most incidents of aspiration result in chemical pneumonitis, or irritation and inflammation of lung tissues caused by an inhaled particulate, and never reach the severity of chemical or infectious pneumonia. When it does, mortality rates can reach as high as 71%. Bacteria establishes its presence quickly, so interventions are needed. Aspiration pneumonia can be considered both a chemically induced pneumonia and an opportunistic infection of the lungs. Inflammatory pulmonary processes occur after abnormal entry of fluids into the lower respiratory tract. The aspirated fluid can be oropharyngeal secretions, particulate matter, or gastric content. The inhaling of inflammation-generating secretions into the lungs is a significant event for a ready pathogen, typically bacterial, to proliferate (Sanivarapu et al., 2022; Sanivarapu & Gibson, 2022; Klompas, 2022).

Parasitic Pneumonia – is the least common of the major pneumonia types. Parasites are all around us, and in us, not just for those living in tropical areas. Typically, pneumonia-causing parasites start somewhere else on or in the body and migrate into the lungs later. Common parasitic types of pneumonia are Toxoplasma gondii (toxoplasmosis), Plasmodium malariae, and Paragonimus westermani, the Asian lung fluke.

The WHO is currently targeting the conditions of pneumonia as the greatest infectious killer of children worldwide. Pneumonia alone accounts for 14% of all childhood deaths of those under 5 years of age. The first line treatment is amoxicillin dispersible tablets (WHO, 2021).

Early diagnosis and aggressive treatment, especially with children, is a priority. Clients tend to wait until late into the onset of pneumonia to present for care. We need to coach clients that when symptoms present, stay away from the internet, come in, and get a quick check.

Urgent care center or physician's office, a good examination, a quick set of labs, and a CXR will generally rule out bronchitis, wayward upper respiratory issues, or other conditions mimicking pneumonia.

Figure 6: Pneumonia Bacteria

The diagnosis of pneumonia was established by the Infectious Diseases Society of America (IDSA) and the American Thoracic Society (ATS) and requires two elements. Those two elements include visualization of a lung infiltrate (by CXR, CT, ultrasound) and the presence of one or more of the major symptoms accompanying pneumonia (cough, fever, shortness of breath, sputum).

Remember, pneumonia is a fight against inflammatory progression and whatever the causative agent is. Once a diagnosis (or even a strong presumption) is established, speedy treatment initiation becomes a priority. While a perfect diagnostic environment would reveal (in the CBC with differential) bacterial versus viral infection (or other), it is better to initiate treatment than to wait. Waiting around for a culture and sensitivity is not a realistic luxury.

Empiric regimens have been established to cover the most common bacterial causes of pneumonia until such a time that an organism's specificity and antibiotic sensitivity are known (File, 2021). Microscopic visualization of respiratory secretions with Gram stain can help narrow down the list of potential pathogens, as can knowing what medical comorbidities are present and awareness of recent travel. Refer to the initial intake interview and evaluation, the true foundation on which all good clinical decisions rest.

The IDSA recommends initial empiric antimicrobial therapy for community-acquired pneumonia until laboratory results can guide more specific therapy.

In outpatient (community) settings, empiric regimens target Streptococcus pneumoniae (the most common), Haemophilus influenzae, Moraxella catarrhalis, and methicillin-susceptible Staphylococcus aureus (MRSA) and include:

• Amoxicillin 1 g PO tid, or
• Azithromycin 500 mg PO one dose, then 250 mg PO daily, or
• Clarithromycin 500 mg PO bid or extended-release 1000 mg PO daily, or
• Doxycycline 100 mg PO bid

These are empiric antibiotic recommendations for inpatient hospital clients, who are often sicker due to other comorbid conditions, as well as the resilience nosocomial infections possess. The focus here shifts toward quick initiation of treatment targeting the most common problematic pathogens seen in this specific client base.

When the empiric therapy shows effectiveness, once culture and sensitivity results return, therapy must continue for at least five days, preferably until the client is afebrile for at least 48 hours. Should a better treatment regimen be revealed by diagnostic studies, switch to that one while weaning off the ineffective therapy (Ayoade, 2022).

Recommendations regarding initial empiric antimicrobial therapy for pneumonia (CAP or HAP) can be used as a guide until laboratory results are in.

In hospital settings, empiric regimens are designed to be initiated within the first four hours of presentation. There is a focus on common pathogens such as Staphylococcus aureus, gram-negative enteric bacilli (e.g., Klebsiella pneumoniae), Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. Troublesome atypical pathogens also include Legionella pneumophilia, Mycoplasma pneumoniae, and Chlamydia pneumoniae.

If there is no suspicion of MRSA or Pseudomonas, empiric treatment recommendations include:

• Levofloxacin 750 mg IV or PO q24h, or
• Moxifloxacin 400 mg IV or PO q24h, or
• Combination of a beta-lactam ampicillin-sulbactam 1.5-3 g IV q6h, with one of the following:
  • Ceftriaxone 1-2 g IV q24h, or
  • Cefotaxime 1-2 g IV q8h, or
  • Ceftaroline 600 mg IV q12h plus Azithromycin 500 mg IV/PO q24h, or Doxycycline 100 mg PO BID

When Pseudomonas are known to be present currently or recently, treatment shifts to include:

• Combination therapy with both an antipseudomonal beta-lactam such as piperacillin-tazobactam 4.5 g IV q6h, or
  • Cefepime 2 g IV q8h, or
  • Ceftazidime 2 g IV q8h, or
  • Meropenem 1 g IV q8h, or
  • Imipenem 500 mg IV q6h

Treatment may include an antipseudomonal fluoroquinolone such as:

• Ciprofloxacin 400 mg IV q8h, or
• Levofloxacin 750 mg IV q24h

If MRSA is, has been, or may be diagnosed with pneumonia, recommendations are to:

• Add vancomycin 15 to 20 mg/kg IV every 8-12h initially and adjust to therapeutic monitoring, or
• Add Linezolid 600 mg IV every 12h (Ayoade, 2022; File, 2021).

Severe cases of pneumonia, those requiring intensive care in an inpatient setting, with or without ventilator support, have a set of empiric treatment regimens pending pathogen and treatment specificity.

In the most intensive settings, empiric regimens target Streptococcus pneumoniae (the most common) and problematic pathogens such as beta-lactamase-producing Haemophilus influenzae, Moraxella catarrhalis, and MRSA. Regimens include:

• Ceftaroline 600 mg IV daily, or
• Cefotaxime 1 to 2 g IV tid, or
• Ceftaroline 600 mg IV bid, or
• Ampicillin-sulbactam 3 g IV qid, or
• Ertapenem 1 g IV daily, plus an advanced macrolide, such as Azithromycin 500 mg IV daily (Ayoade, 2022; File, 2021).

Once a specific pathogen with its best treatment becomes identified, it is imperative to switch to the better, more targeted treatment. Should clinical findings reveal that pneumonia is not the primary distressing condition (i.e., findings of heart failure, myocarditis, pulmonary edema, lung cancer) or that the pneumonia is chemical or viral in nature, stop the empirical antibiotics and treat the actual cause. Abrupt antibiotic cessation may be warranted due to individual circumstances; however, tapering off the unneeded empiric treatments is also acceptable. Good judgment based on individual client factors and needs is always the best protocol.

Treating pneumonia may be summed up as killing the organism once it is identified using antibiotics, antivirals, antiparasitics, or antifungals). If a chemical or irritant is identified, neutralize it (flush it out, use anti-inflammatory agents, encourage healing). The goal is to keep the client breathing!

Treating the inflammation of the lung tissue is as, or even more crucial, than dealing with the cause of pneumonia. So, think about the following (Cunha, 2022; Drugs.com, 2022; Pruitt, 2021; Hess, 2022):

• Rest
• Adequate fluids
  • If oral, encourage warm beverages, which may help relax airways
  • IV fluids
• Antipyretics (fever reducers)
  • NSAIDs
  • Acetaminophen
  • Aspirin – not for children due to the risk of Reye's syndrome
• Antitussive medications to help control coughing
• Chest physiotherapy
• Expectorants, mucolytics, bronchodilators, warm moist air – steamy baths, showers, humidifiers, nebulizers
• Avoid further lung irritants – stay away from air pollution, second-hand smoke, pollen, and such
• Oxygen therapy –supplemental oxygen and oxygen bolstering techniques such as airway clearance exercises and airway clearance mechanical aids
  • Techniques and exercises include pursed lip exhaling, huff coughing, and postural drainage.
  • Mechanical ventilatory support if needed. Be cautious about using low tidal volumes when dealing with respiratory failure secondary to bilateral pneumonia or acute respiratory distress syndrome (ARDS).
  • Other mechanical aids include high-frequency chest wall oscillation (HFCWO) vests, percussion devices, and positive pressure cough assist devices.

Take prescribed medications during recovery! Some pathogens require an extended course of antibiotics to assure complete clearance from the lung tissues. Other medications, such as mucolytics, play a significant role as the body works to clear debris from clogged alveoli. Should your client have difficulty getting their medications in, take time to explore why. Often, simple fixes such as flip-top pill organizers will make a world of difference toward medication compliance.

Fluids help loosen mucous and prevent dehydration. Unless prohibited by another condition, such as heart failure, drink up! Warm soups and hot beverages are great choices, as they aid in breaking up mucous and offsetting dehydration. Avoid cold beverages as they may increase mucous production and bronchospasms (Daruvuri, 2021).

Healing is arduous work! The body is working to repair tissues and membranes in the most exquisitely crafted organ system of the body. That takes metabolic energy, resources, and rest. If a cough suppressant would aid sleep, check with the physician. Yes, lung debris needs to be expelled. However, the rest required for healing must balance against taking out the trash. Putting a humidifier in the bedroom or a hot steamy shower before bed will do wonders to aid troubled breathing.

Heavy meals can be difficult during recovery, so plan on frequent healthy snacks. Carbs, proteins, and healthy fats are all excellent choices for speeding recovery. Carbohydrates help provide quick, easily digested energy needed for healing. Proteins provide the building blocks for cell structure repair, including producing substances required for an active immune system. Green leafy vegetables add vitamins and antioxidants to the healing process.

Many pathogens contribute to the inflammatory condition of pneumonia. For some of these, there are organism-specific vaccines, take Covid, for example. In the United States, three specific PCVs and one interesting outlier have been approved for use (EverydayHealth, 2021).

Young children may receive PCV13. Remember that pneumonia is the number one infectious cause of death in those under five. Oh, the "13" stands for the number of pneumococcal types that the vaccine, PCV13, protects against!

• Typically, PCV13 is dispensed to infants and young children in four doses. At ages 12-15 months, and 2, 4, and 6 years old.
• It is effective for older children, through age 5 years, if not started when younger.
• Adolescents and older children 6-18 years may receive an adjusted dose of PCV13 if they missed inoculation earlier.

• For adults 19 years of age and older, there are options.
  • A single dose of PCV15, followed by a dose of pneumococcal polysaccharide vaccine (PPSV23), or
  • A single dose of PCV20 (U.S. Department of Health and Human Services, 2022)

We discussed previously that the thick polysaccharide coating around the Streptococcus bacteria makes it challenging to recover from pneumonia. Researchers have developed an immunization that uses bits of that coating to ready the human immune system to recognize that wall of protection (EverydayHealth, 2021). It is a welcomed adjunct in the fight against pneumonia!

Local providers or regional public health officials may recommend the vaccine for specific high-frequency pathogens. These include (Musher, 2022):

• SARS-CoV-2 vaccine
• Influenza
• Haemophilus influenza type B (Hib)
• Pertussis
• Tuberculosis
• Measles
• Varicella (chickenpox)

Prevention includes avoiding chemicals that irritate the alveoli of the lungs, and alveoli are fussy!

• Avoid smoking! Both your own and from others, and yes, this includes cannabis.
• No vaping; also, avoid second-hand vaping.
• Dodge city smog, air pollution in general.
• Any powders snorted up the nose, just say no. Your respiratory system will thank you.

Hand washing is always number one when it comes to controlling unwanted pathogens. Soap and a good scrub under warm running water are effective. Use alcohol-based hand sanitizers if no other option is available.

When sneezing or coughing, do so into a tissue (then dispose of it) or the bend of your elbow; then wash your hands.

Avoid touching your face as much as possible, especially during influenza season.

Being healthy and seeking the joy of good physical health go a long way toward prevention. Exercise, eat healthy and well, and strive for that optimal weight. If chronic health issues are present, do your best to work around them, take needed medications, and hesitate to add unnecessary medications, both prescription and over-the-counter. New mothers, breastfeed if possible. Excellent health benefits come to both you and your child.