common cold
TRANSCRIPT
Liliana Rios, M.D. – PGY-1
July 24 - 2008
CASE: Mr. Sniffle, 35 y.o. male
• complaining of feeling tired and achy for few days
• today: congested, thick yellow nasal discharge
• non-productive cough started this morning
• no fever
• requesting an antibiotic
• wants to know what OTC products will work for his symptoms
QUIZ
What is the most likely diagnosis?
a. influenza
b. acute bacterial sinusitis
c. the common cold
d. pneumonia
e. asthma
QUIZ
What is the most likely diagnosis?
a. influenza
b. acute bacterial sinusitis
c. the common cold
d. pneumonia
e. asthma
Definition: the common cold
benign self-limited syndrome
caused by members of several families
of viruses
Mild upper respiratory viral
illness
Symptoms: the common cold
Day 1: sore or “scratchy” throat, +/- low grade fever
Day 2-3: nasal obstruction, rhinorrhea, sneezing
• thick purulent nasal discharge does NOT mean bacterial sinusitis!
Day 4-5: cough becomes bothersome, nasal symptoms less severe
• Average duration: 3-7 days
• Virus-induced changes in airway reactivity can persist for up to 4 weeks
Symptoms: the common cold*
Day 1
* Epidemiol Infect 1993 Aug;111(1):143-56
Symptoms: the common cold*
Day 2 to 3
* Epidemiol Infect 1993 Aug;111(1):143-56
Symptoms: the common cold*
Day 4 to 5
* Epidemiol Infect 1993 Aug;111(1):143-56
• thick purulent nasal discharge does NOT mean bacterial sinusitis!
QUIZ: the common cold
What is the most common culprit?
a. rotavirus
b. coronavirus
c. rhinovirus
d. echovirus
e. influenza virus
QUIZ: the common cold
What is the most common culprit?
a. rotavirus
b. coronavirus
c. rhinovirus
d. echovirus
e. influenza virus
50%
15%
15%
5%5% 10% Rhinovirus
Coronavirus
Influenza
RSV
Parainfluenza
Adeno, Entero
Virology *4,5
* 4 Lancet 2003 Jan 4;361(9351):51-9. * 5 Lancet Infect Dis. 2005 Nov;5(11):718-25.
Seasonal Patterns
Fall, late spring : RhinovirusParainfluenza
Winter, spring: RSV, coronavirus
Summer: Enterovirus (year)
Adenovirus: Outbreaks in Military facilities daycare centers, hospital
Facts: the common cold
• Incubation period 24 to 72 hours• Average duration 3 – 7 days•Virus-induced changes in airway reactivity can persist for up to 4 weeks(Rhinovirus )• 2 to 3 episodes /per year*
*Ann Allergy Asthma Immunol 1997 Jun;78(6):531-9;
Diferential diagnosis: the common cold
•Allergic or seasonal rhinitis •Bacterial pharyngitis or tonsillitis (Centor criteria) •Sinusitis •Influenza
But how do I know it’s just a cold?
COLD INFLUENZA
Fever Rare 39-40o
Headache Rare Usual
Myalgia Mild Severe
Malaise Mild May last 3 wks
Extreme fatigue Unusual Usual
Nasal congestion Common Common
Sneezing Common Sometimes
Sore throat Common Common
Chest discomfort/ cough
Mild Mod-Severe
Facts: Influenza
•Patients with illnesses which involve the cardiovascular or pulmonary systems •Patients with diabetes mellitus, renal disease, hemoglobinopathy, or immunosuppression
•Residents of nursing homes or chronic care facilities
•Otherwise healthy individuals over age 50
Facts: Influenza Vaccine
All of the mentionated before
Plus
Health care workers
Pregnant women in second or third trimestrer
But how do I know it’s just a cold?
• Acute Bacterial Sinusitis
• complicate 0.5-2% of colds
• Diagnosis = persistent URTI with no improvement >10-14 days OR worsening after 5 days +
• nasal congestion/ purulent nasal discharge
AND
• facial pain
But how do I know it’s just a cold?
• Pneumonia =
1. 2 of: fever, new cough, pleuritic chest pain, SOB +
2. Auscultatory findings +
3. New opacity on CXR
•Asthma
Airway reactivity*1
Vs
Acute asthma attacks exacerbationsUp to 40% of viral upper resp infection*2
*1 Am J Respir Crit Care Med 1995 May;151(5):1666-73; discussion 1673-4. *2 Chest 1997 Sep;112(3):591-6.
Complications Sinusitis:
Acute bacterial sinusitis develops in 0.5 to 2.5 percent of adult patients after viral *1
Lower respiratory tract disease :
RSV, elderly (CHF) and immunocompromised
Acute otitis media: Eustachian tube dysfunction;
*1 J Allergy Clin Immunol 1998 Sep;102(3):403-8.
QUIZ: the common cold
Mr. Sniffles wants to know if his girlfriend will catch this if he kisses her. You tell him the virus is:
a. Likely to transmit by kissing
b. Unlikely to transmit by kissing
QUIZ: the common cold
Mr. Sniffles wants to know if his girlfriend will catch this if he kisses her. You tell him the virus is:
a. Likely to transmit by kissing
b. Unlikely to transmit by kissing*
* Prim Care 1996 Dec;23(4):657-75
FACTS: transmission*
• Hand –to- hand
• most efficient = direct contact
• virus can survive for 2 hours on human skin
• also aerosol
• NOT via saliva – kissing is OK!
(in 90% of people with colds, no detectable virus in saliva) *Epidemiol Rev 1988;10:243-58.
FACTS: the common cold
• you can be re-infected by the same virus, but subsequent illness will be milder and shorter *1
• NO evidence that cold climate increases susceptibility to respiratory illness *2
*1 Am J Epidemiol 1989 Feb;129(2):319-40.
*2 Prim Care 1996 Dec;23(4):657-75.
FACTS: the common cold
• huge economic burden
• annual work absence in the US = 23 million lost days/ year*1
* Arch Intern Med. 2003 Feb 24;163(4):487-94.
Therefore …
• huge potential for drug companies to make big money!!
• 1 in 4 US adults had taken a cough or cold medication in the last 7 days
• in Canada, >700 OTC cough and cold medications
QUIZ: the common cold
Mr. Sniffles only wants to spend his money on treatments that he can be sure will help his symptoms. What do you suggest?
a. Antibiotics
b. Antihistamine
c. Codeine
d. Dextromethorphan
e. Pseudoephedrine
f. D. or E.
g. None of the above – just rest and fluids
QUIZ: the common cold
Mr. Sniffles only wants to spend his money on treatments that he can be sure will help his symptoms. What do you suggest?
a. Antibiotics
b. Antihistamine
c. Codeine
d. Dextromethorphan
e. Pseudoephedrine
f. D. or E.
g. None of the above – just rest and fluids
Treatment: the common cold
• the ONLY “A” recommendation is NOT to use antibiotics to treat the common cold.*1
• everything else is “B” (inconsistent or limited quality evidence)
*1 Cochrane Database Syst Rev. 2005 Jul 20;(3):CD000247.
Treatment: what might work
COUGH:
• dextromethorphan (DM) – cough suppressant
• Cochrane review: 2 studies: benefit, 1 study: no benefit *1
• guaifenesin (Benylin E, Robitussin) – expectorant
•1 study: benefit, 1 study: no benefit
Treatment: what might work
NASAL CONGESTION:
• topical or oral decongestant (pseudoephedrine = Sudafed) *1
• small benefit of single dose, NO benefit of repeated use over several days
• topical intranasal Atrovent (0.06% spray) *2
• 2x 42ug sprays per nostril TID-QID x 4 days
• decreased nasal discharge by 26% : only 1 study, expensive
• humidified air and fluid intake *3
• inconsistent results, but no harm!
*1 Cochrane Database Syst Rev 2004;(3):CD001953*2 Cochrane Database Syst Rev 2004;(3):CD001953*3 Arch Fam Med. 1998 Jan-Feb;7(1):39-43.
Treatment: what WON’T work
COUGH:
• codeine – works for chronic cough, NOT for acute cough*1
• antihistamines – no benefit*2
*1 Chest. 2006 Jan;129(1 Suppl):72S-74S*2 Chest. 2006 Jan;129(1 Suppl):72S-74S
Treatment: what WON’T work
NASAL CONGESTION:
• Antihistamines *1
• no benefit, significant adverse effects
• Saline nasal spray
• no benefit
*1 J Gen Intern Med 1996 Apr;11(4):240-4.
Treatment: the common cold
COMPLEMENTARY/ ALTERNATIVE:
• Vitamin C *1
• no effect if started after onset of symptoms
• inconsistent results if started before: may slightly decrease cold duration if 200mg daily
• Exercise *2
• decreased incidence in overweight postmenopausal women who exercised 5x/week
*1 Cochrane Database Syst Rev. 2007 Jul 18;(3):CD000980. *2 Am J Med. 2006 Nov;119(11):937-42.
Treatment: the common cold
COMPLEMENTARY/ ALTERNATIVE:
• Echinacea *1
• no evidence in well-designed studies
• Zinc *2
• inhibits viral growth in vitro
• inconsistent study results
*1 Cochrane Database Syst Rev. 2006 Jan 25;(1):CD000530. *2 Laryngoscope. 2006 Feb;116(2):217-20.
Case Conclusion: Mr. Sniffle
• you reassure Mr. Sniffle that he has just a common cold
• you educate him about why antibiotics are not a good idea
• after you expound upon the evidence (or lack of) for various remedies, he chooses to try intranasal atrovent
• you also suggest hydration, rest, and not to waste his money on OTC products