upper respiratory tract infections Flashcards
How many types of microorganisms lives in the human mouth ?
~ 700 kind
Gram positive ones are Streptococcus mutans & pneumoniae, Staphylococcus aureus. Gram negative ones are H. influenzae & Neisseria spp.
About 85 spp of fungi, particularly
Candida spp
What is responsible for the Humoral immunity of upper airway ?
Immunoglobulin A
What is responsible for the innate immunity of upper airway ?
Resident macrophages, monocytes,
neutrophils, eosinophils.
What is the annual incidence of common cold ?
- Children 3-8 viral resp illnesses per year.
- Adults 2-4 colds
- > 60yoa fewer than 1
cold/year.
when does Pharyngitis peaks in children ?
4 to 7 years
What is the trend of paediatric Epiglottitis?
Occurs in children aged 2-7 years and peaks at age 3.
What is the tend of Laryngitis & laryngotracheobronchitis?
Occurs from 6 months to 6 years and peaks at age 2.
What are the seasonal trend of various URTIs ?
- Rhinovirus- b/w March and October.
- Coronavirus- b/w Jan and april
- Adenovirus- Throughout the year
- parainfluenza virus type 3: March and July.
- parainfluenza virus type 4: August and November.
- RSV: between Jan to May and November and December.
- Influenza: Jan to March and november to decemeber.
- GAS: Jan to May and Nov to December.
What are the modes of spread of URTIs ?
- droplet, fomite, aspiration and direct spread.
What is the main cause of common cold ?
Rhinovirus serotypes.
What are the symptoms of URTIs ?
- Conjunctivitis can occurs rarely with adenovirus.
- Nasal discharge and congestions are common.
- Sneezing and Sore throats are very common.
- Mild to moderate hacking cough is common.
- Headache is rare and fever can occur in children but not in adults.
- Malaise, fatigue, and weakness and slight myalgia can occur sometimes.
- Symptoms typically resolves in 3 to 14 days.
What are the symptoms of Influenza ?
- Sometimes soreness behind the eyes and conjunctivitis may occur.
- Nasal discharge is common.
- Nasal congestion, sore throat, and sneezing can sometimes occur.
- Cough, headache, fever lasting for 3 to 4 days with chills are very common.
- Malaise, fatigue, and myalgias are common.
- 7 days of symptoms with cough and fatigue lasting for additional days.
What are the pharmacological approaches for common cold ?
- Analgesics + combo products containing antihistamines and decongestants.
Honey should not be prescribed for children under the age of 1. why ?
Due to risk of botulism
What are the subtypes of influenza virus?
Influenza A, B and C
What is the influenza virus that most commonly cause influenza ?
influenza virus A
How does influenza virus enter the respiratory tissue ?
It uses Haemagglutinin to bind to the sialic acid through the receptor sites and triggering viral entry.
What is the action of viral neuroamnidase ?
NA cleaves sialic acid from cell surface and progeny virions facilitating virus release from infected cells and infection spread.
What is the incubation period of influenza and its symptomatology ?
1 to 14 days. It can cause the spread of URTI to LRTI. It is associated fever and systemic symptoms not seen in common cold.
What is the clinical presentation of Influenza ?
If it is sudden onset, the patients present with Chills,Fever, Generalized
aches & pains, Headache. If it is gradual onset Sore throat, dry cough and coryza progressing to persistent cough +/- productive cough. In both sudden and insidious forms rarely nausea, vomiting, and abdominal pain can occur.
what is the dX workup in Influenza ?
- It is a clinical diagnosis.
- In hospital setting PCR may be done for clinical decision making and ruling out COVID-19.
*If LRTI suspected chest X-Ray maybe needed.
What is the Tx of Influenza ?
- Symptomatic therapy (same as common cold)
- NO ASPIRIN if < 18 years old (Reye’s Syndrome)
- Antiviral therapy in SELECT patients
What is the most common cause of sinusitis ?
It is mostly viral and only symptomatic treatment is done. Bacterial sinusitis are relatively rare.
What are the investigations in Sinusitis ?
- It is usually a clinical diagnosis.
- When investigation is needed for patients presenting with co-occuring conditions like orbital cellulitis:
- Sinus X-ray
- CT sinuses
- Sinus aspirate for culture
