Case Study Essay: Diagnosing Upper Respiratory Tract Infection Based on Symptoms

The symptoms displayed by the 21-year-old student, which include a sore throat, fever, muscle aches, and abrupt rhinorrhea, indicate an upper respiratory tract infection. Pathogens known to cause this as a differential diagnosis include Rhinovirus-caused viral upper respiratory infections (common cold), Human Coronavirus, and Influenza.
Streptococcus pyogenes, a group A streptococcus, causes bacterial upper respiratory tract infections.
A type 1 allergic reaction is allergic rhino-pharyngitis.
To get a solid diagnosis, the practitioner must compare and contrast the signs and symptoms of each disease's etiological agent. Allergic rhino-pharyngitis is manifested by rhinorrhea, sneezing associated with allergic conjunctivitis symptoms e.g. tearing and eye itchiness. The symptoms occur upon exposure to specific allergens and can be seasonal. Atopic conditions are not infectious hence cannot be transmitted by coming into contact with affected persons.

Streptococcal rhino-oro-pharyngitis will present with oro-pharyngeal mucosae inflammation, fevers and submandibular or sub-mental lymphadenopathy. Rarely does strep sore throat present with rhinorrhea. Laboratory investigation done by throat swab for microscopy shall reveal the offending pathogen i.e. Group A streptococcus by the use of a gram stain smear or through swab sample culture.

Viral upper respiratory infections including influenza, rhinoviruses and coronaviruses may present with acute onset upper respiratory symptoms of rhinorrhea, sneezing, oral-pharyngitis and fever (temperature > 37.5 degrees Celsius). Influenza virus have a common presentation of severe myalgia in infected patients. The mode of transmission being person-person contact with aerosols and droplets from infected individuals and the short incubation period makes it the most likely diagnosis.

Question 2.

Influenza virus and rhinoviruses bind to the epithelial cells of the upper respiratory tract mucosa including the nasal cavity and the oral-pharynx. The viral particles contain glycoproteins Neuraminidase and Hemagglutinin that help the virus to bind to the host’s target cells in the respiratory tract. Subsequently, the viral particles inject DN into host cells and replicate producing new virions that exit the cell to infect more mucosal epithelial cells. The infected cells produce excessive pro-inflammatory cytokines and chemokines that mediate the immune response responsible for the disease’s symptoms e.g. rhinorrhea, sneezing, sore throat, muscle aches, and fever.

Question 3.

In the clinical set up, Common cold viral infections including influenza infection can be diagnosed via its presenting symptoms. These include the presence of a history of sudden onset running nose, dry cough, fever, muscle aches and malaise especially after coming into contact with persons known to have been suffering from common cold or with similar symptoms (Arrol). A physical examination of the nasal and oral-pharyngeal mucosa shall reveal inflammation and increased secretions leading to nasal blockage and rhinorrhea.

Isolation of the virus for nucleic acid studies are rarely done as routine.

Question 4.

Common cold due to rhinoviruses and Influenza is the most common infectious disease in the world and affects people of all races. On average, adults experience approximately 4 episodes of common cold per year while school going children suffer over 15 episodes yearly. This represents an average of 30million flu cases per year worldwide (G, S and W). Different influenza virus strains tend to acquire differing virulence from one strain to another hence differing abilities to produce epidemics. In the USA, hospitalizations due to flu infections averaged at 200,000 hospitalizations per year in 2014 alone.

Transmission of common cold viruses occurs via contact with infected material e.g. aerosols and secretions from infected persons. These can be picked from inanimate objects like tables and working surfaces that have been contaminated. Person to person spread via handshakes and hand to surface routes form a main route of spread of common cold. Subsequently, the viral particles gain access to the upper respiratory tract mucosa where it replicates within the epithelia cells lining the nasal and oral-pharyngeal cavities.

Question 5.

Common cold due to rhinoviruses and influenza has no known cure or treatment. The infection has an acute onset of symptoms that are self-limiting in nature subsiding within 5-7days of the onset of infection. As a result, treatment is always aimed at mitigating and alleviating the concomitant symptoms of common cold. For example, non-steroidal anti-inflammatory drugs e.g. Paracetamol, Brufen and Diclofenac can be used to relieve headaches, fever and muscle aches. The inflammatory responses that lead to rhinorrhea can be treated with anti-histamine drugs e.g. cetirizine. Oral rehydration therapy is key in treatment of the malaise associated with flu (De, Kummar and Lesslar).

Epidemics of influenza viruses that have occurred in the following zoonosis of avian flues have led to efforts being made towards the development of influenza and other flu virus vaccines. These can be administered to those at risk of disease e.g. the elderly, immuno-compromised individuals like the HIV patients, and those living in regions prone to epidemics (Hay, Gregory and Douglas).

Question 6.

The difficulties encountered by drug manufacturers arise from the fact that there exist hundreds of influenza and rhinovirus strains that are pathogenic to humans. Additionally, these viruses undergo rapid mutational changes that render them resistant to novel drugs. Finally, the body’s immune mechanisms against common cold viruses is short lived hence there’s no long-term memory immune cells that can mediate a host immune response to a viral agent exposure. This makes vaccine production difficult (Jefferson, Di and Rivveti). Besides this, the rapid mutations of virus strains can lead to a fast spread of an infection especially when virulent pathogenic strains emerge and cause epidemics as experienced in the 1918 when an influenza pandemic led to the death of over 10 million people.

Question7.

Novel treatments that may be useful in symptomatic relieve may include the use of nasal irrigation wish normal saline to reduce nasal congestion and rhinorrhea. The use of honey as a cough reliever by soothing the throat and as a possible anti-viral agent can be worthy trying. Zinc lozenges have an advantage of enhancing epithelia cell regeneration following infection by influenza viruses hence shorten the symptomatic periods. Steam inhalation can relief nasal and para-nasal sinus secretions and the associated congestion. Exercise has been deemed to be an effective reliever of congestion. Its mechanism of actions is yet to be known.

Isolation of sick individuals especially those who have symptoms of flu infections main serve to contain the spread of virus to other people especially in schools and other social places where people live in close proximity.

Works Cited

Arrol, B. "Common Cold: Clinical Evidence." PMID (2011): 1510.

De, Sutter, et al. "Oral antihistamine-decongestant-analgesic combinations for the common cold." Pub Med (2017): 12.

G, Wong, Shu S and Shi W. "Epidemiology, genetic recombination, and pathogenesis of coronaviruses." Trends in Microbiology (2016): 490-502.

Hay, A, et al. "The Evolution of Human Influenza Virus." Philosophical Transacions of The Royal Society (2013): 1861-70.

Jefferson, T, Pietrntoni Di and C Rivveti. "Vaccines for Preventing Influenza for Healthy Adults." The Cochrane Database of Systematic Reviews (2014): 56-60.