Clinical notes on Pneumonia UNZA 5th year lecture.pptx

The university of Zambia clinical notes on pneumonia

1. Pneumonia Dr. Chalomba Chitanika University of Zambia

2. Outline

3. Disclaimer

4. Case Scenario A 45 year old man comes in complaining of a productive cough for 3 days. He admits to having a fever. He has no shortness of breath ,chest pain or palpitations. His past medical history is significant for diabetes He does not consume alcohol or smoke tobacco Temperature is 38.2 ,Pulse is 112 bpm, Respiratory rate is 36/minute, BP is 105/76 mmHg He is fully conscious. His physical exam reveals a dull percussion note with bronchial breath sounds on the right. He has nasal flaring and is using his accessory muscles to breathe What is the most important next step? Check his oxygen saturation Order a chest x-ray Ask for a sputum sample Start giving antibiotics Give him Oxygen

5. Definition

6. Pathophysiology The lung and tracheobronchial tree are usually sterile below the level of the larynx an infecting agent must reach this site via a breach in host defences micro-aspiration haematogenous spread, direct spread from an adjacent structure Inhalation activation of previously dormant infection (TB)

7. Classification and Epidemiology Community Acquired Pneumonia Hospital Acquired Pneumonia (>48 hrs of hospitalisation) Importance of classification: Aetiology of the two is different, therefore this classification dictates how you mange the patient Hospital acquired infections tend to be resistant to the widespread antibiotics

8. Other things to consider

9. Classification of Community Acquired Pneumonia Typical – S. pneumoniae ,H. influenzae, Moraxella catarhallis , Klebsiella pneumoniae Organisms have a cell wall and can therefore be seen on gram stain of respiratory specimens Respond to beta lactam antibiotics Atypical- Leigionella , Coxiella, Mycoplasma, Viruses (including COVID-19) Organisms have no cell wall so cannot be seen on gram stain Tendency for extra-pulmonary features Do not respond to beta lactams so this dictates treatment

10. Clinical Picture - Symptoms Symptoms of Pneumonia General Respiratory Fever Rigors Malaise Anorexia Cough Shortness of breath Chest pain N.B. Extrapulmonary features depend on the type of pneumonia e.g. Diarrhea, Vomiting, Rash, Anaemia, Arthritis, Dysgeusia

11. Clinical Picture - Signs Signs of Pneumonia General Respiratory Pyrexia Confusion Tachycardia Hypotension Inspection: Cyanosis, Tachypneoa , intercostal in drawing, Accessory muscle use Palpation: Reduced Expansion, Increased tactile fremitus Percussion: Dull note Auscultation: Bronchial Breath Sounds, Crackles

12. Investigations

13. Investigations cnt’d Sputum Microscopy, Culture,Sensitivity Acid Fast Bacilli and Gene Xpert Special Investigations Urine: Streptococcus, Leigionella PCR (when viral pneumonia is suspected) Cold agglutinin test (Mycoplasma) Pleural Fluid culture Bronchoscopy (in the case of slow resolving pneumonia or suspected TB and a patient is unable to submit sputum)

14. Chest X-ray

15. Assessment of Severity

16. Principles of Treatment Aetiological Treatment Depends on suspected causative organism (Cause is never found in ~50% of patients, most common cause is S.Pneumonia so antibiotics are given empirically) Bacteria: Antibiotics Viruses: Antivirals etc. Oxygen Support Aim for SpO2 of 94-98% or 8 kPa of PaO2 IV fluid support Needed due to Anorexia, Dehydration and Shock Best option is a crystalloid Venous Thromboembolism prophylaxis Patients are usually immobilised and at risk of DVT More actual in COVID-19 pneumonia Analgesia

17. Antibiotic therapy Choice of treatment is guided by: Community Acquired vs. Hospital Acquired Other circumstances : Aspiration, Immunosuppression etc.

18. Clues to Aetiology Clinical Setting Probable Cause Lobar pneumonia of a cute onset elderly ,immunosuppressed Streptococcus pneumoniae Post influenza, IV drug use, underlying lung disease Staphylococcus auerues Cavitary pneumonia of the upper lobes in elderly, alcoholics or diabetics Klebsiella Pneumoniae Flu like symptoms, dry cough, high fever, smell or taste disturbances COVID-19 Pneumonia Dry cough and flu like symptoms after exposure to air conditioning systems Legionella Pneumonia Dry cough and severe exertion dyspnoea in a severely immunosuppressed patient Pneumocystis Carini pneumonia Unresolving cough with fever, night sweats, weight loss and anorexia, cavities in the upper lobes (HIV- ve ) Pulmonary Tuberculosis

19. Typical Regimens for Typical Community Acquired Pneumonia S. pneumoniae H. influenzae M. catarrhalis K. pneumoniae

20. Atypical Community Acquired Pneumonia Causative Organism Classic Clinical Picture Treatment of Choice Mycoplasma Pneumoniae Flu –like symptoms and dry cough Clarythromycin or Doxycylcine or Floroquinolone Leigionella Pneumophilia Flu-like symptoms, dry cough,dyspnea Flouroquinolone or Doxycycline Chlamydophila Pneumophila URTI (Otitis and pharyngitis) then pneumonia Doxycycline or Clarithromycin Chlamydophyla Psitacci Contact with birds( esp parrots), headache,fever,dry cough,D and V Doxycycline or clarithromycin Viral Pneumonia (Influenza, measles, CMV, Coronavirus) Upper respiratory symptoms, fever, rash Supportive therapy, Antivirals Pneumocystis jiroveci Dry cough,fever and exertional dyspnea in the immunosuppressed Septrin or Pentamidine or clindamycin/primaquine +/- Steroids

21. Hospital Acquired Pneumonia

22. Aspiration Pneumonia

23. Complications of Pneumonia

24. Poor prognostic factors

25. Differential Diagnosis Pulmonary embolism Pulmonary oedema Bronchial carcinoma Bronchiectasis Eosinophilic pneumonia Foreign body Alveolar haemorrhage Cryptogenic organizing pneumonia, Vasculitis Connective tissue disease Drug-induced lung disease

26. References Jameson JL, Fauci AS, Kasper DL, Hauser SL, Longo DL, Loscalzo J, eds. Harrison's Principles of Internal Medicine. 20th ed . McGraw Hill; 2018. Ian B. Wilkinson, Tim Raine, Kate Wiles, Anna Goodhart, Catriona Hall, Oxford Handbook of Clinical Medicine 10th Edition ;2017 Kumar, P. and Clark, M., Kumar & Clark's clinical medicine 9 ed . 2016 Stephen Chapman Grace Robinson, John Stradling, Sophie West , Oxford Handbook of Respiratory Medicine 2nd Edition ,2009