Post on 07-May-2015
description
Dr. Ashish V. Jawarkar
Diseases of the Respiratory System
Dr. Ashish V. Jawarkar
The Upper Respiratory System
Consists of:NosePharynx (throat)
Middle earEustachian tubes
Dr. Ashish V. Jawarkar
The Lower Respiratory System
Consists of:LarynxTracheaBronchial tubes
AlveoliPleura
Dr. Ashish V. Jawarkar
Upper Respiratory System defense
•Coarse hairs in the nose filter large particles from air entering the respiratory tract.•The ciliated mucous membranes of the nose and throat trap airborne particles and remove them from the body.•Lymphoid tissue, tonsils, and adenoids provide immunity to certain infections.
Dr. Ashish V. Jawarkar
Dr. Ashish V. Jawarkar
Lower respiratory tract defense
The lower respiratory system is usually sterile because of the action of the ciliary escalator.
Microorganisms hoping to infect the respiratory tract are caught in the sticky mucus and moved up by the mucociliary escalator.
Dr. Ashish V. Jawarkar
Upper Respiratory System Diseases
Most respiratory tract infections are self-limiting.
Often caused by bacteria & viruses in combination
Dr. Ashish V. Jawarkar
Upper Respiratory System Diseases
Pharyngitis: inflammation of the pharynx
Laryngitis: swelling and irritation (inflammation) of the voice box (larynx)
Tonsillitis: inflammation of the tonsils
Sinusitis: inflammation of the sinuses
Dr. Ashish V. Jawarkar
Agents of URTi
S. pneumonia – pharyngitis/tonsillitisS. Pyogenes – pharyngitis / tonsillitisC. diphtheria - diptheriaB. pertussis – whooping coughCommon cold – rhino virus
Dr. Ashish V. Jawarkar
Streptococcal Pharyngitis
Also called strep throat
Streptococcus pyogenes / strep. pneumoniae
Gram positive cocci chains
Dr. Ashish V. Jawarkar
Corynebacterium Diphtheriae
Gram positive club shaped rod
Dr. Ashish V. Jawarkar
Dr. Ashish V. Jawarkar
Dr. Ashish V. Jawarkar
Diphtheria
Diphtheria membrane: Fibrin, tissue, bacterial cells
•Leading infectious killer of children in U.S. in 1935•Leading infectious killer of children in U.S. in 1935
Dr. Ashish V. Jawarkar
Diphtheria
Still common in developing countries where immunizations aren't given routinely.
Up to 40% to 50% of those who don't get treated can die.
The exotoxin inhibits protein synthesis, and heart, kidney, or nerve damage may result.
Prevented by DTP vaccine
Dr. Ashish V. Jawarkar
Lab diagnosis
Microscopy – Gram’s , Albert’sCulture – selective media containing tellurite,
Loeffler’s serum slope
Dr. Ashish V. Jawarkar
Pertussis / whooping cough
Causes whooping cough
Mostly in childrenCoughing thru
strained vocal cords produces sound
Dr. Ashish V. Jawarkar
diagnosis
Mostly clinicalBacteria does not grow on ordinary mediaPrevented by vaccination – DPT
Dr. Ashish V. Jawarkar
Bacteria, viruses, and fungi causeBronchitis – S. pneumoniaePneumonia – S. pneumoniae,
Klebsiella, MycoplasmaTuberculosis - M. tuberculosis
Lower Respiratory System Diseases
Dr. Ashish V. Jawarkar
Mycoplasma
Bacteria with no cell wallsGram negative, better stained with Giemsa
stain
Dr. Ashish V. Jawarkar
Grow on media enriched with serumColonies give fried egg appearance
Dr. Ashish V. Jawarkar
Mycoplasmal Pneumonia
Primary atypical pneumonia; walking pneumonia No physical signs/symptoms X ray shows lower lobe pneumonia
Genitourinary infections
Dr. Ashish V. Jawarkar
Dr. Ashish V. Jawarkar
Viral Pneumonia
Viral pneumonia occurs as a complication of influenza, measles, or chickenpox
Viral etiology suspected if no other cause is determined
Dr. Ashish V. Jawarkar
Respiratory Syncytial Virus (RSV)
The most common viral respiratory disease in infants; 4500 deaths annually
Causes cell fusion (syncytium) in cell cultureSymptoms: Pneumonia in infantsDiagnosis: Serological test for viruses and
antibodiesTreatment: Ribavirin, palivizumab
Dr. Ashish V. Jawarkar
Influenza (Flu)
Symptoms: Chills, fever, headache, and muscle aches No intestinal symptoms
1% mortality, very young and very oldTreatment: Zanamivir and oseltamivir inhibit
neuraminidaseProphylaxis: Multivalent vaccine (currently
grown in Embryonated egg cultures
Dr. Ashish V. Jawarkar
The Influenza Virus
Hemagglutinin (HA) spikes used for attachment to host cells
Neuraminidase (NA) spikes used to release virus from cell
Dr. Ashish V. Jawarkar
Fungal Infections
Fungal spores are easily inhaled; they may germinate in the lower respiratory tract.
The incidence of fungal diseases has been increasing in recent years.
The mycoses can be treated with amphotericin B.
Dr. Ashish V. Jawarkar