The document provides information on various respiratory tract infections including their classification, anatomy, defenses, risk factors, causes, pathophysiology, clinical presentation, diagnosis, and treatment. It discusses common upper respiratory infections such as rhinitis, common cold, sinusitis, pharyngitis, laryngitis, tonsillitis and their epidemiology. For each infection, it describes the etiological agents, signs and symptoms, complications and recommended treatment approaches.

1. Internal Medicine
Respiratory Tract Infections
Pendame

2. Objectives
• To learn the epidemiology and various clinical presentation
of URT
• To identify the common etiological agents causing these
syndromes
• To study the laboratory diagnosis of these syndromes
• To determine the antibiotic of choice for treatment

3. Introduction
• Common condition that affect most people on occasion.
• Some infections are acute that symptoms last for several days.
• Others are chronic with symptoms with symptoms that last for long
time or recur.
• Patients seldom require hospitalisation.

4. Classification of respiratory tract infections
1. Upper respiratory tract
2. Lower respiratory tract

5. Respiratory Tract anatomy

6. ANATOMY REVISION CONT.

8. The Respiratory Tract and Its Defenses
• Most common place for infectious agents to gain access to the
body
• Upper respiratory tract: mouth, nose, nasal cavity, sinuses,
pharynx, epiglottis, larynx
• Lower respiratory tract: trachea, bronchi, bronchioles, lungs,
alveoli
Defenses
• Nasal hair
• Cilia
• Mucus
• Involuntary responses such as coughing, sneezing, and
swallowing
• Macrophages

9. Defenses of the Respiratory System

10. Classification of upper respiratory tract
infections
• Tonsillitis
• Rhinitis(The common cold)
• Pharyngitis
• Epiglottitis
• Acute laryngitis
• Acute laryngotracheobronchitis
• Sinusitis
• Peri-Tonsillar &Retro – pharyngeal abscess
• Otitis externa, otitis media and mastoiditis

11. Risk factors for URTI
• Close contact with children: both daycares and schools increase the
risk for URI
• Medical disorder: People with asthma and allergic rhinitis are more
likely to develop URI
• Smoking is a common risk factor for URI
• Immunocompromised individuals including those with cystic fibrosis,
HIV, use of corticosteroids, transplantation, and post-splenectomy are
at high risk for URI
• Anatomical anomalies including facial dysmorphic changes or nasal
polyposis also increase the risk of URI

12. RHINITIS
• A group of disorders characterised by inflammation and irritation of
the mucous membranes of the nose.
• Classified as: a) non allergic
b) allergic
Rhinitis may be an acute or chronic condition.

13. Causes of Rhinitis
Allergic Rhinitis
• Pollen
• Dust mites
• Mold
• Animal
• Dander
Non allergic Rhinitis
• Rhinoviruses,
• Adenoviruses,
• Respiratory Syncytial virus (RSV)
• Coxsackie's
• Viruses.

14. Pathophysiology
• Nonallergic may be caused by a variety of factors including
environmental factors such as changes in temperature or humidity,
odors, or foods; infections; age; systemic disease; drugs (cocaine) or
prescribed medications (Anti hypertensive, oral contraceptives; or the
presence of foreign body

15. Cont…
Rhinitis may also be manifested of an allergy.
There are same pathological processes involved in rhinitis and sinusitis.
Mucous membranes lining the nasal passages become inflamed,
congested, and oedematous.
The swollen nasal conchae block the sinus openings, and mucous is
discharged from the nostrils.
Sinusitis is also marked by inflammation & congestion, with thickened
mucous secretions filling the sinus cavities and occluding the
openings.

16. Clinical manifestation
• Rhinorrhea (excessive nasal discharge, runny nose).
• Nasal congestion
• Nasal discharge (purulent with bacterial rhinitis)
• Nasal itchiness
• Sneezing
• Headache may occur if sinusitis is also present.

17. management
• Depends on the cause ie minimise exposure to allergies.
• Corticosteroids may be required.
• Management focuses on symptom relief;Antihistamines for
sneezing,itching and rhinorrhea
• Oral decongestant
• Ophthalmic agents

18. Viral rhinitis(common cold)
• The term “common cold” often used when referring to upper
respiratory tract infection that it is self-limited & caused by a virus
(viral rhinitis)
• Characterised by nasal congestion, rhinorrhea, sneezing, sore throat
and malaise.
• Term “cold” refers an afebrile, infectious, acute inflammation of
mucous membrane of the nasal cavity.
• Colds are highly contagious because the virusis shed for about 2 days
before the symptoms appear & during the first part of the
symptomatic phase.

19. cause
Six viruses known to produce the S&S;
Rhinovirus
Parainfluenza virus
Coronavirus
Respiratory syncytial virus (RSV)
Influenza virus and
Adenovirus

20. Cont..
• Each virus may have multiple strains ie;
there are over 100 strains of rhinovirus which accounts for 50% of all
colds.

21. Clinical manifestation
• Nasal congestion
• Runny nose
• Sneezing
• Nasal discharge
• Nasal itchiness
• Tearing watery eyes
• “scratchy” or sore throat
• General malaise
• Low grade fever
• Chills
• Headache
• Muscle aches

22. Cont…
• Cough usually appears as illness continues.
• It can exacerbates the herpes simplex commonly called the cold sore.
• Symptoms last from 1 – 2 weeks

23. management
• No specific treatment
• Symptomatic therapy.
• Provide adequate fluid intake
• Encourage rest
• Prevent chilling
• Increase intake of vitamin c
• Use expectorants as needeed
• Warm & salt water gargles sooth the sore throat
• NSAIDS i.e Aspirin or ibuprofen
• Anti histamines
• Topical nasal decongestants

24. Complications
• Acute otitis media,
• Pharyngitis,
• Sinusitis,
• Conjunctivitis,
• Pneumonia,
• Adenitis.

25. ACUTE SINUSITIS
• It is an infection of the paranasal sinuses less than 4 weeks
• Sinuses,mucus lined cavities filled with air that drain normally into the
nose,are involved in a high proportion of URTI.
• If their openings into the nasal passages are clear, the infections
resolve promptly
• However,if their drainage is obstructed by the deviated septum or by
hypertrophied turbinates, spurs or nasal polyps or tumors, sinus
infection may persists to purulent discharge.

26. Cont…
• Some people are prone to sinusitis because of occupation i.e
exposure environmental hazards such as paint, sawdust, chemicals
that cause chronic inflammation of the nasal passages.

28. Pathophysiology
• Develops as a result of an URTI such as unresolved viral or bacterial
infection or an exacerbation of allergic rhinitis.
• Nasal congestion caused by inflammation, oedema & transudation of
fluid, leads to obstruction of the sinus cavities.
• This provides an excellent condition for bacterial growth.
• Organisms are S.pneumoniae, H.influenzae, moraxella catarrhalis
• Dental infection also have been associated with acute sinusitis.

29. Clinical manifestations
• Facial pain
• Pressure over affected sinus affected
• Nasal obstruction
• Fatigue
• Purulent nasal discharge
• Fever
• Headache
• ear pain

30. Cont…
• Dental pain
• Cough
• Decreases sense of smell
• Sore throat
• Eyelid edema
• Facial congestion or fullness
It is difficult to differentiate from URI or Allergic rhinitis

31. Management
• Treat infection -Amoxicilin, Augumentin
-Azithromycin, Quinolones
• Shrink the nasal mucosa – use of oral & topical decongestant
• Antihistamines if allergy is suspected e.g.chlopheniramine
• Relieve the pain
• Surgical intervention is reserved for patients with intra cranial
complications such as abscess or orbital involvement

32. Complications
• Meningitis
• Brain abscess
• Ischeamic infarction
• Osteomyelitis
• Orbital cellulitis

33. CHRONIC SINUSITIS
• Is an inflammation of the of the sinuses and lining of nasal passages
that persists for more than 12 weeks in an adult and 2 weeks in a
child.
• The diagnosis requires at least two of four cardinal signs/symptoms
(mucopurulent drainage, nasal obstruction, facial
pain/pressure/fullness, and decreased sense of smell)

34. Pathophysiology
• Narrowing or obstruction in the ostia of the frontal, maxillary, and
anterior ethmoid usually causes chronic sinusitis, preventing
adequate drainage to the nasal passages.
• This combined area is known as the osteomeatal complex.
• Blockage that persists for greater than 3 weeks in an adult may occur
because of infection, allergy,or structural abnormalities.

35. Pathophysiology
• This results in stagnant secretions, an ideal medium for infection. The
organisms that cause chronic sinusitis are the same as those
implicated in acute sinusitis.
• Immunocompromised patients are at increased risk for developing
fungal sinisitis.
• Aspergillus fumigatus is the most common organism with fungal
sinusitis

36. Clinical manifestation
• Impaired mucociliary clearance & ventilation
• Cough ( thick discharge constantly drips backward into the nasal
pharynx)
• Chronic hoarseness
• Chronic headaches in the periorbital area,and facial pain.
• Symptoms are common in the morning.

37. Clinical manifestation
• Fatigue
• Nasal stuffiness
• Decrease in smell
• Decrease in taste
• Fullness in the ears

38. Medical management
• Same as of acute sinusitis (amoxyl,augumentin,ampicillin,quinolones)
• Decongestant
• Antihistamines
• Oral cortcosteroids
• Anti fungals in suspected
• If medical management fails surgical intervention ie(excising &
cauterisation of nasal polyp)

39. Complication
• Severe orbital cellulitis
• Subperiosteal abscess
• Cavernous sinus thrombosis
• Meningitis
• Encephalitis
• Ischemic infarction

40. PHARYNGITIS
• An inflammation or infection in the throat, usually causing symptoms
of a sore throat.
• The most common viruses causing pharyngitis belong to the
adenovirus group, which consists of about 32 serotypes.
• Endemic adenovirus infection causes the common sore throat, in
which the oropharynx and soft palate are reddened and the tonsils
are inflamed and swollen.
• Within 1-2 days the tonsillar lymph nodes enlarge.
• It is usually precedes illness of colds and flu that doesn’t require
antibiotics unless otherwise caused by bacterial infection because
most disappear by their own in weeks or less.

41. Incubation Period
• Acute Pharyngitis is 72 hours.
• Sub-acute Pharyngitis is 2-3 days.
• Chronic pharyngitis is 7-10 days.
• Recurrent Pharyngitis is 1-2 weeks.

42. Causative Agents
1. Bacteria (Streptococci, Staphylococci)
2. Virus (Adenovirus, Mononucleosis)
3. Allergens (dust, mist, pollens, smokes)
4. Alcohol
5. Use of tobacco

43. Causative agent enters the upper
respiratory tract, causing inflammation of
the pharynx.

44. Pathophysiology
• The body responds by triggering an inflammatory response in the
pharynx.
• This results in pain,fever,vasodilation, edema and tissue damage,
manifested by redness & swelling in the tonsillar pillars,uvula & soft
palate.
• A creamy exudate may be present in the tonsillar pillars

45. Clinical Manifestation
I. Pharyngitis with colds
• Sneezing
• Cough
• Low fever
• Mild headache
II. Pharyngitis with flu
• Fatigue
• Body aches
• High fever
• Chills

46. Clinical Manifestation
III. Pharyngitis with bacterial infection
• Enlarges lymph nodes in neck &
armpit
• Headache
• Anorexia
• Swollen spleen
• Swollen tonsils
• Liver inflammation
• Dysphagia
• Red & edematous pharynx with
exudates
IV. Pharyngitis with viral infection
• Sore throat
• Coryza (inflammation of the nasal
cavities mucous membrane)
• body malaise & fatigue
• hoarseness of voice
• Low-grade fever

47. Treatment
• Saline gargle (Mouth wash if needed)
• Analgesics (Brufen) or Antipyretics (Paracetamol)
• Increase fluids but not soft drinks & not too sweet juices
• Removal of allergens
• Antiobiotics (Penicillin is drug of choice)
• Benzanthine 1.2MU IM stat OR
• Amoxycillin 500mg tds x 7/7or Erythromycin 500m qid x7/7
• Vitamin-C for viral infection as the case don’t need medication for it disappear by
its own.
• Hospitalization if cannot swallow fluids to provide I.V. hydration.
Note:
• Avoid amoxicillin and ampicillin if there is a possibility of infectious
mononucleosis (characterized by a triad of fever, tonsillar pharyngitis, and
lymphadenopathy)
• Viral pharyngitis is treated with supportive measures since no effect of antibiotics

48. Laryngitis
• Is the inflammation of the larynx due to
• overuse, irritation, infection (bacterial & viral),and non-infectious
agents (mist, pollens, dews, sandstorms, dust, chemicals, smokes)
• That can be acute, sub-acute, and chronic.

49. Incubation period:
• Acute laryngitis is 72 hours.
• Sub-acute laryngitis is 2-3 days.
• Chronic laryngitis is 4-10 days.
• Recurrent laryngitis is 2-3 weeks.

50. Causes
Acute Laryngitis
1.Virus infection (colds, measles)
• colds secretions enter the larynx via nasopharynx & caused
inflammation
2.Voice overuse
• over talking dries the larynx tissues causing irritation and
inflammation
3.Bacterial infection (diptheria)
• airborne microorganism invades the larynx & caused inflammation

51. Causes ct..
II. Chronic Laryngitis
• Irritants inhalation
• Chronic sinusitis
• Acid reflux (gastroeasophageal)
• Excess alcohol intake
• Smoking

52. Clinical features
• Hoarseness
• Other symptoms and signs of URI, including rhinorrhea, nasal
congestion and cough
• Sore throat, Dry throat

53. Treatment
• Humidification, Increase fluids
• Voice rest
• Antibiotics are not recommended except when group A streptococcus
is cultured
• Chronic laryngitis usually requires biopsy with culture.
• Avoid smoking, recreational drugs, and alcohol

54. Tonsillitis & adenoiditis
• Is the inflammation of the tonsils
• Tonsils are made –up of adenoids tissue that secretes lymphocytes
that help in fighting against systemic infection of the body.
• Tonsils are composed of lymphatic tissue and are situated on each
side of the oropharynx.
• The faucal or palatine tonsils and lingual tonsils are located behind
the pillars of fauces & tongue, respectively.
• They frequently serve as the site of acute infection (Tonsillitis)

55. Cont…
• Chronic tonsillitis is less common and may be mistaken for other
disorders such as allergy, asthma, & sinusitis.
• Adenoids or pharyngeal tonsil consists of lymphatic tissue near the
center of the posterior wall of the nasopharynx.
• Infections of the adenoids frequently accompanies acute tonsillitis.

56. Incubation period
• Acute Tonsillitis is 72 hours.
• Sub-acute tonsillitis is 2-3 days.
• Chronic Tonsillitis is 4-6 days.
• Recurrent Tonsillitis is 1-2 weeks.

57. Aetiology
• This can either be bacterial or viral
• Group A beta-streptococcus is the most common organism associated
with tonsillitis & adenoiditis.
• Acute tonsillitis can either be bacterial or viral in origin.
• Sub acute tonsillitis is caused by the bacterium Actinomyces. Chronic
tonsillitis, which can last for long periods if not treated, is mostly
caused by bacterial infection.

58. Clinical Features
• Sore throat as referred pain to the ears
• Painful or difficult swallowing (Dysphagia)
• Crouch coughing
• Headache, fever, chills
• Red swollen tonsils with pus
• Swelling and tenderness of the submandibular glands

59. Inflammation to the tonsils.

60. Diagnosis
• Physical examination
• Culture & sensitivity on site for bacterial
• Clinical features
Diagnostic procedures:
• Buccal swab for Culture & sensitivity test to identify streptococci and
staphylococci infections
• Complete blood count for elevated white blood cells & lymphocytes

61. Management
Penicillin is he drug of choice
• Benzanthine penicillin 1.2 MU single dose i/m.
• Alternatively Oral penicillin –Amoxicillin 500mg tds x 7/7 ( needs
compliance)
• Alternatively Erythromycin 500m qid x7/7
• Analgesics.
• Tonsillectomy if medical treatment has failed & recurrent tonsillitis
• Saline gargle ( mouth wash)

62. Complications
• Peritonsillar abscess (tonsils with pus)
• Lemierres syndrome (septicemia)
• Hypertrophy of tonsils (snoring, mouth breathing, disturbed sleep
and obstructive sleep apnea)
• Rheumatic heart disease
• Glomerulonephritis
• Tonsillolith (tonsil debris in whitish color)
• Halitosis (bad breath)

63. Other Upper respiratory Tract Infections
Reading assignment
• Epiglottitis
• Acute laryngo tracheobronchitis
• Peri-Tonsillar and Retro – pharyngeal abscess
• Otitis externa, otitis media and mastoiditis