ALOK SINHA Department of Medicine Manipal College of Medical Sciences Pokhara , Nepal
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Transcript of ALOK SINHA Department of Medicine Manipal College of Medical Sciences Pokhara , Nepal
ALOK SINHADepartment of Medicine
Manipal College of Medical SciencesPokhara, Nepal
UPPER RESPIRATORY TRACT INFECTIONS
• The upper respiratory tract includes • nose• paranasal sinuses• pharynx• upper part of the larynx above the level of the
true vocal cords
Infections of the Upper Respiratory TractSite Disease AgentsNasal cavity Coryza (common cold) Many different viruses
Chronic atrophic rhinitis Bacteria (Klebsiella ozaenae) Rhinoscleroma Klebsiella rhinoscleromatis Invasive fungal infections Mucor, Aspergillus Nasal diphtheria Corynebacterium diphtheriae Mucocutaneous leishmaniasis Leishmania braziliensis Syphilis (tertiary) Treponema pallidum Lepromatous leprosy Mycobacterium leprae Rhinosporidiosis Rhinosporidium seeberi
Paranasal sinusesAcute sinusitis Pyogenic bacteriaChronic sinusitis Pyogenic bacteriaAspergilloma ("fungus ball") Aspergillus species
Pharynx, tonsil Acute pharyngitis Many different viruses Streptococcus pyogenes
Diphtheria Corynebacterium diphtheriae Pharyngeal gonorrhea Neisseria gonorrhoeae Peritonsillar abscess (quinsy) Pyogenic bacteriaInfectious mononucleosis Epstein–Barr virus
Retropharyngeal space Abscess Pyogenic bacteriaTuberculosis Mycobacterium tuberculosis
Larynx Acute laryngitis Many different virusesAcute epiglottitis and laryngitis Haemophilus influenzae
Which specialty should treat & there for teach
these diseases?
.
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The Common Cold
CORYZA
An estimated 2 of every 5 persons are affected each year (40%)
World population: 6,775,235,741 40% of this = 2,710,094,296
Some experience multiple episodes in 1 year
Rhinoviruses: most common agents Over 100 serotypes have been implicated
Other viruses implicated included coronaviruses influenza C parainfluenza virus adenoviruses respiratory syncytial virus
• Highly contagious: 75% of patients infected with Rhinovirus will have symptoms
• Respiratory droplets spread by sneezing, coughing hand contact with
nose, eyes, or face Fomite - Skin cells, hair, clothing (hanky) bedding
Contributing factors: Change in weatherLoss of sleepGoing outside with wet hairFatigue
Signs and symptoms Incubation period: 2 – 4 days
May last from 6 – 10 days or possibly up to 3 weeks after incubation period
• Initial complaints • sneezing • clear, watery rhinorrhea
@ nasal obstruction • general malaise but no fever
• Subsequently• Headache• nasal congestion• scratchy throat
After 2 – 3 days• nasal discharge becomes thicker, cloudy,
and yellowish in color • systemic symptoms improve• Hoarseness, cough, and sore
throat may last up to 7 – 10 days
Diagnosis: Made on clinical grounds
• Pt’s symptoms• nasal exam showing
reddened, edematous mucosa narrowed nasal passages watery discharge
Laboratory and/or imaging only indicated if other conditions are strongly suspected
Viral isolation/culture is not practical
Treatment
No curative treatment Supportive therapy – 10 treatment
• Rest• Fluids & humidification• Decongestants (Phenylephrine - α1-adrenergic receptor
agonist)
• Analgesics• Cough suppressants• Mucolytics• Antihistamines
Short term use of zinc lozenges (zinc gluconate 10-15 mg q 2 hrs) shown to reduce duration of subjective symptoms if begun early in course of disease
Zinc Gluconate
Role of antibiotics
Antibiotics should be considered if symptoms last longer than 10-14 days (secondary bacterial infection)
Inappropriate prescribing of antibiotics is common• Due to patient beliefs/misinformation of
cold being bacterial in origin
?
PharyngitisPharyngitis
May be of bacterial or viral origin Most common cause Rhinovirus
• Self-limiting; usually lasts 3-4 days Group A, beta-hemolytic strep is
the primary bacterial pathogen
in 1/3 cases - early detection reduces incidence of
Signs and symptoms: Inflammation of pharynx & lymphoid
tissue results in • Fever & malaise • sore throat• rhinorrhea • Tonsillar exudates
• Anterior cervical adenopathy There is usually a lack of cough
Diagnosis On PE: observe throat for tonsillar
exudates; obtain throat swab Rapid streptococcal identification tests
are most commonly used • Sensitivity – 80% • Specificity – 95%
Throat cultures may be collected if rapid strep screen is negative
Management/Treatment: Symptomatic treatment
• salt-water gargles • throat lozenges • Acetaminophen• cool-mist humidification
Antibiotics treatment necessary to treat proven strep infections• Benzathine penicillin G 1.2 million units as a
single dose, is optimal therapy• For pen – allergic pts,
erythromycin 500mg po QID x 10 days Azithromycin 500mg once daily x 3 days
Acute epiglottitis Acute epiglottitis
Bacterial cellulitis of the epiglottis (supraglottis) and/or surrounding tissue
Caused by:• Haemophilus influenzae type b (HiB)- most
likely • H. parainfluenzae and streptococci some times
Average age of onset: 1–5 years old• In most adults the disease is less severe and
of slower onset
Clinical Features Sudden onset of
• Sore throat• Fever• Head forwardly extended, usually with
drooling Stridor - present
Pharyngeal visualization (w/ EXTREME caution) shows a ‘Cherry red' epiglottis
Neutrophil leucocytosis Epiglottis culture usually (+) for HIB
• result takes long time Blood cultures frequently (+) for HIB in children
• organisms fewer than in meningitis Lateral X-Ray neck-
• enlarged hypopharynx • forward neck extension
• with “thumbprinting” of epiglottitis
Epiglottitis- Differential diagnosis
Angioneuropathic edema of supraglottic structures
Anaphylaxis Caustic ingestion Thermal burns of epiglottis Infectious mononucleosis Laryngotracheitis Blunt Trauma
Treatment
• Intubation is often required, but usually discontinued in less than 24h
• Early antibiotic treatment and intubation may
prevent the need for tracheostomy
• Steroids to reduce inflammation and avert tracheostomy- unproven but used
• Tracheostomy: may be required in life threatening conditions
Drug treatment• #1 Ceftriaxone
(or cefotaxime, cefuroxime)
• Others - Ampicillin and Sulbactam• Ticarcillin disodium and clavulanate potassium • piperacillin/tazobactam • levaquin • Gatifloxacin
• Amoxicillin should not be used due to noted resistance
Prevention
HiB vaccination early!!!• Prior to HiB, there were roughly 20 K cases
of HiB disease each year (U S data)
• Post-vaccine era = incidence has decreased by 95%.
Prophylaxix: Family Members, day-care workers,
health-care workers • Rifampin 300 mg q12h x 2d
Acute laryngitisAcute laryngitis
Healthy Vocal Cords Healthy vocal
cords have smooth straight edges
Normal healthy vocal cords • pearly-white color • in contrast to thepinkish surrounding tissue
Causes
Viral (70-80%)
Group A beta-haemolytic streptococcus (20-30%)
Often a complication of acute coryza
• Dry sore throat • Hoarse voice or loss of voice• Attempts to speak cause pain• Initially painful and unproductive cough • Stridor in children (croup) because of
inflammatory oedema leading to partial obstruction of a small larynx
Croup (Laryngotracheobronchitis) is a group of respiratory diseases that often affects infants and children[
Complications rare Chronic laryngitis• Downward spread of infection may cause
• Tracheitis• Bronchitis • Pneumonia
Treatment Rest voice Paracetamol 0.5-1 g 4-6-hourly for relief
of discomfort and pyrexia Steam inhalations may be of value Antibiotics not necessary in simple acute
laryngitis
Influenza Influenza
First recorded pandemic in 1580
Possible accounts in 412 BC
Destroyed Charlemagne's army in 876 A.D.
Killed thousands in 1647
Flu
21 million people died worldwide out of a billion infected (total world population at that time 1.8 billion)
Possible end to war
1918-1919 Spanish Flu pandemic
8.5 million people died in World War I
2009 (H1N1) flu pandemic dataArea Confirmed
deaths
Worldwide (total) 14,286European Union and EFTA 2,290
Other European countriesand Central Asia
457
Mediterranean and Middle East 1,450
Africa 116
North America 3,642
Central America and Caribbean 237
South America 3,190
Northeast Asia and South Asia 2,294
Southeast Asia 393
Australia and Pacific 217
Note: The proportion of confirmed deaths within total deaths due toA/H1N1 is unknown
Swine Flue (H1N1)Swine Flue (H1N1 Influenza)
Answer these two questions Is the Influenza or Flu caused by
“Influenza” virus What H. Influenza is
?
Etiology
• caused by a group of myxoviruses- • common types
• A
• B• C
Influenza A (H1N1) virus is a subtype. causes • endemic in pigs – swine influenza • and birds – avian influenza new H1N1 strain of swine-origin caused pandemic
• New influenza viruses are constantly being produced by mutation
• antigenic drift: – small changes in surface antigen
• antigenic shift: – acquire new antigens by
reassortment between avian/swine & human strains
Transmission
Swine influenza virus common throughout pig populations worldwide
Transmission from pigs to humans is not
common and does not always lead to human influenza
• People with regular exposure to pigs are at increased risk of swine flu infection– Meat of an infected animal poses no risk of infection
when properly cooked
• Transmission from one person to another is by droplet or fomite
Mild symptoms : • Fever• sore throat & cough• headache, muscle or joint pains• nausea vomiting, or diarrhea
Those at risk of a more severe infection:• asthmatics • diabetics • obesity • heart disease • immunocompromised• pregnant women
Symptoms in severe cases : Difficulty breathing or shortness of breath Pain or pressure in the chest or abdomen Sudden dizziness Confusion Severe or persistent vomiting Low temperature
Complications
Abigail & Brittany Hensel March 7, 1990
Some patients deteriorates around 3 to 5 days after onset
• Respiratory failure requiring immediate admission to an intensive
care unit & mechanical ventilation• myocarditis & collapse - some times
Diagnosis Should not wait for laboratory confirmation
• Diagnosis based on clinical & epidemiological background & start treatment early
For Confirmation a nasopharyngeal or oropharyngeal tissue swab tested with • Real-time or RT-PCR
not required in most people with flu symptoms. test results do not affect recommended course of treatment
For diagnosis of influenza and not H1N1/09 flu more widely available tests:
Rapid influenza diagnostic tests (RIDT): results 30 minutes • high rate of false negative
patients should be treated empirically based on the level of clinical suspicion
Direct & indirect immunofluorescence assays (DFA & IFA): take 2–4 hours
The flu virus is constantly mutating
Humans will probably never be immune from the flu
Natural immunity is not very strong
Role of immunization
Influenza immunization
Not 100% effective
Scientists choose the predominant strains
Chosen the year before
Swine flu vaccines
1. Nasal spray vaccine released in early October 2009 • live attenuated H1N1 virus
approved for use in healthy individuals age 2 - 49
not be used in pregnancy or immunocompromised
2. Injectable vaccine • Made from killed H1N1
used from 6 months to the elderly including pregnant females
Antiviral agents Oseltamivir (Tamiflu) and zanamivir
• used to prevent or reduce influenza A and B symptoms
• Efficacy reduces if the flu symptoms already have been present for 48 hours or more
Supportive measures in severe infection • ventilation support • treatment of other infections like pneumonia
Prophylaxis Avoid crowded places Well ventilated houses Covering mouth & nose while coughing /
sneezing Avoid touching nose & eyes
Frequent hand washing
That’s all in this session !