CASE PRESENTATION

MGT OF PNEUMONIAby

DR TASIE OBINNANATIONAL ASSEMBLY CLINIC, ABUJA.7 SEPT 2015.OVERVIEWIntroductionEpidemiologyClassificationCausesPathophysiologySymptoms and signsDiagnosisInvestigationTreatmentComplicationDifferential diagnosisConclusionINTRODUCTIONInflammatory condition affecting the lung parenchyma due to acute microbial infection with at least one opacity on chest radiograph. ORAcute respiratory illness associated with recently developed radiological pulmonary shadowing which may be segmental, lobar or multilobar.EPIDEMIOLOGYCommon illness seen in general outpatient clinic. Pneumonia is the second major killer of Nigerian children with 17% infant mortality per year, yet our fathers and mothers are ignorant of its causes and prevention.In a prospective cohort study in Ilorin, the rate of pneumonia was 2 episodes per child per year as compared with South East Asia( 0.36 episodes/ child/ year), European regions ( 0.06 episodes/ child /year).In Bronchopneumonia, rates are greatest in children less than 5yrs and adults older than 65yrs, occuring frequently in developing world than in developed world.Rudan et al calculated and published the 1st global estimate of incidence of clinical pneumonia. More than half of the world annual new pneumonia cases are concentrated in just five countries: India, China, Pakistan, Bangledesh and Nigeria.CLASSIFICATIONSITE: lobar or bronchopneumoniaAETIOLOGY: infective , chemical, allergic, PREVIOUS HEALTH: CAP, Nosocomial pneumonia , immunocompromised.CLINICAL PRESENTATION: typical or atypical.ATYPICAL PNEUMONIAaka Interstitial pneumonitis.Inflammation is in the alveolar septa and interstitium, there is no exudate in the alveolar space.caused by viruses and mycoplasma pneumonia in majority of cases.Symptoms are milder and longer lasting than typical pneumonia.Histology: chronic inflammatory cells in the alveolar wall and interstituim with pink hyaline membrane lining the alveolar walls.COMMUNITY ACQUIRED PNEUMONIAInfectious lung disease involving the alveoli, distal airways and the interstituim of the lungs , contracted outside the hospital setting.Affects 4 million adults yearly.Severity is determined by host factor , not pathogen type and virulence.Most gram negative bacteria that cause CAP are enterobacteria [ S.pneumonia, H.influenza] and enter the lungs via inhalation of vomits.HOSPITAL ACQUIRED PNEUMONIAaka nosocomial infection.Refers to new episode of pneumonia occurring at least 2days after admission to hospital and not incubating at the time of admission.Highest rates among ICU patients undergoing mechanical ventilation.The most important distinction between hospital and community acquired pneumonia is the difference in the spectrum of the pathogenic organism.CAUSESBACTERIA eg : Strep pneumonia, Chlamydia pneumonia, Mycoplasma pneumonia, Legionella pneumophilia, H. influenza, Staph aureus, Klebsella etc.VIRUSES eg : Rhinovirus, Coronavirus, Adenovirus, Parainfluenza, Human simplex virus. Human simplex virus rarely causes pneumonia except in groups such as newborn, person with cancer, transplant recipients and significant burns patients.3. FUNGI eg Histoplasma capsalatum, C.immitis, C.neoformans, Aspergilloses, Candidiasis( rare), Sporotrichosis.4. PARASITIC causesT.gondii, Ascaris lumbricoides, Hookworm and S.stercoralis.PREDISPOSING FACTORS Smoking.Chronic alcoholism.Asthma.Chronic obstructive airway disease.Old age.Recent cold or flu.Immunodeficiency state.Male gender.Use of acid suppressing medications like proton pump inhibitor/ H2 blocker, steroid therapy10. Contaminated ventilator system or equipments.11. Aspiration of oropharyngeal contents into the lower respiratory tract.12. SepsisPATHOPHYSIOLOGYBacteria typically enter the lungs with inhalation, though they can reach the lung via the blood stream if other part of the body are infected.Often bacteria live in the upper respiratory tract and are continually being inhaled into the alveoli. Once inside the alveoli, bacteria travel into the spaces between the cells and also between adjacent alveoli through connecting pores.BACTERIA AND FUNGIInvasion of the lungs by bacteria and fungi causes cellular death and triggering of the immune system leading to phagocytosis of the bacteria by neutrophils.Cytokines released by neutrophils causes exudation of fluid inside the alveoli.The neutrophil, bacteria debris and the exudates in the alveoli result in impaired oxygen transportation.Sepsis may occur from bacteremia.Septic shock may occur and leads to damage in multiple parts of the body.PATHOPHYSIOLOGY contd.Viral infections occur when contaminated airborne droplets are inhaled through the mouth or nose. Some viruses such as measles and Human simplex virus may reach the lung via the blood. The invasion of the lungs may lead to varying degrees of cell death. When the immune system responds to the infection , even more lung damage may occur.PARASITEEnters the body through skin or swallowing.Migrates to the lungs most often through the blood.Both mechanism of cellular destruction and immune response result in disruption of oxygen transportation.Immune response is mediated by eosinophil.STAGES 1. CongestionThe affected lung parenchyma is partially consolidated and red purple. Occurs on Day1/2. On microscopy, there is vascular engorgement, few neutrophils and bacteria in the alveoli. 2. Red hepatization seen on Day 3/4The pulmonary lobe appears consolidate, red brown, dry, firm with liver like consistency. Microscopically, there is accumulation in the alveolar space of exudate rich in fibrin mainly with leucocytes, erythrocytes and bacteria.contd of STAGES. 3. Gray hepatization occur on Day 5-7The affected lungs have a liver like consistency with uniform gray color. On cut surface, you would see grayish purulent liquid drains. 4. Resolutionbegins on Day 8 and continues for 3weeks while the exudates within the alveolar spaces will be drained through lymphocytes and airways.SYMPTOMS/ SIGNSCough: productive or non productive. sputum may be whitish , yellowish or greenish.Fever: moderate/ high grade. Fatigue.Pleuritic chest pain: stabbing pain aggravated or worse on deep inspiration or coughing.Difficulty in breathing.Confusion.Headache.Loss of appetite.DIAGNOSIS1) History2) Physical Examinationa) Respiratory examTachypnea i.e. respiratory rate> 18c/mDecreased chest expansion on the affected side. Increased vocal resonance. Dull percussion note. Bronchial breath sounds. Fine / coarse crepitation on the affected side.INVESTIGATION.Chest Xray38yr old patient with M.pneumonia chest xray film showing vague ill defined opacity in the left lower lobe.

XRAY FINDINGS IN LEGIONELLA PNEUMONIA

LOBAR PNEUMONIA XRAY FILM

Legionella pneumonia is implicated in 2- 15% of Community acquired pneumonia. Mild infection may manifest with bilateral involvement but in severe infection , lung agitation and bulging of the fissure have been reported.INVESTIGATIONS2. Sputum M/C/S3. Full blood count. increased WBC is noted> 11,000 cells/ microliter.4. Urine ELISA : legionella5. Pleural fluid M/C/S: mycoplasma, chlamydia, coxiella.6. Blood culture.7. Pulse oximetry: simple non invasive method of measuring arterial oxygen saturation, and assist in monitoring oxygen therapy response.Rare lab testHigh resolution computed tomograghy [ HRCT] can pick up opacities even if chest xray is normalPCR Amplification of the DNA or RNA of micro organism can be used to detect legionella, mycoplasma, and chlamydia pneumonia.OBJECTIVES The main objectives of investigating patients with a clinically based diagnosis of pneumonia are: Obtain radiological confirmation of diagnosis. Obtain a microbiological diagnosis. Assess the severity Identify the development of complications.INDICATION FOR ADMISSIONCURB 65C- confusionU- blood urea nitrogen >7mmol/lR- respiratory rate> 30cycles/minB- diastolic blood pressure 65years.TREATMENTAntibiotics is the drug of choice for treating pneumonia. They include : PARENTERAL INFUSION.IV Ceftriazone 1g dailyIV Erythromycin 500mg qds [ if mycoplasma or legionella is suspected].IV Augmentin 1.2g bdIV Flucloxacillin 1g tds [ if staph is implicated] IV antibiotics can be changed to oral therapy when : WBC is returning toward normalThere are two normal temperature readings [