Clinical case study: bronchiolitis in a one-year-old female

M.C. is a 1-year-old female child who was admitted to the hospital five days ago with respiratory distress and hypoxemia. On the day of admission, M.C. had a fever, an oxygen saturation of 94%, dry cough, breath sounds with crackles and wheezing, sneezing, and a reduced appetite. At the time of assessment, M.C. had not had a bowel movement for two days, but she has only been drinking whole milk, not eating any solids. A CBC and basic metabolic panel were completed on the patient. M.C.'s labs were all normal. No past traumas or pre-existing conditions were reported. M.C. is current on all recommended scheduled childhood vaccinations.

Incidence of Medical Diagnosis

Diagnosis was largely based on symptom presentation. "Bronchiolitis usually presents as one-or-two day history of upper respiratory tract infection. When the lower respiratory tract becomes involved, the hypersecretion of mucus causes the moist cough, commencement of respiratory distress and resultant feeding difficulties. The ability to feed in an infant is an important marker of the severity of bronchiolitis; therefore a well-documented history of any change in feeding is vital" (Kelsall-Knight, 2012). M.C.'s parents indicated that she had not been eating food, though she had been drinking whole milk, and she had not had a bowel movement in two days. "Tachypnoea and tachycardia are usually in proportion to the severity of the illness and infants who are estimated to be feeding less than half of their normal amount usually have oxygen saturations of less than 94 per cent in room air" (Kelsall-Knight, 2012). M.C.'s oxygen saturation was at 94% at the time of admission, but had risen to 98% on the day of care.

Genetic Implications

There are not genetic implications for RSV and bronchiolitis in infants; RSV is a virus and is not a genetic disease or condition. However, it may be somewhat congenital, as there is some evidence that low maternal Vitamin D levels during pregnancy and low Vitamin D levels at birth may contribute to an infant's susceptibility to RSV (Maxwell et al., 2012). "Although protein-energy malnutrition is often cited as the primary contributor to increased infection susceptibility, micronutrients such as vitamin D are increasingly being examined for their role in warding off infection" (Maxwell et al., 2012). Because of this possible link, if M.C.'s mother intends to have future pregnancies, she might be advised about Vitamin D intake during those pregnancies.

Pathophysiology of Medical Diagnosis

RSV generally refers to two strains of the RSV virus. "A member of the iamuy Paramyxoviridae, RSV is an enveloped, nonsegmented, negative-strand RNA virus…RSV is generally transmitted through direct, close contact with large-particle droplets in the coughs or sneezes of an infected person. RSV remains viable on surfaces such as doorknobs and toys for several hours and on the hands from about half an hour up to 12 hours. As a result, infection spreads easily when people rub their eyes or nose after touching an infectious secretion. Humans are the only source of infection" (Todd et al., 2010). Most children will experience at least one RSV infection before the age of two, and in most cases it is mild. However, some children, generally those with compromised immune systems, may experience serious, even life-threatening infections (Todd et al., 2010). Perhaps the most critical piece of information about RSV is that it is infectious for an extended period of time. "Infants and children infected with RSV usually show symptoms within 4 to 6 days of infection. Most will recover in 1 to 2 weeks. However, even after recovery, very young infants and children with weakened immune systems can continue spreading the virus for 1 to 3 weeks" (Todd et al., 2010).

Analysis of Laboratory and Diagnostic Tests / Values

An X-ray of the chest was ordered for two purposes; they can sometimes verify an RSV bronchiolitis diagnosis and they can be used to rule out comorbid pneumonia. A chest x-ray is a picture of the chest that shows the heart, lungs, airway, blood vessels, lymph nodes, spine, breastbone, ribs, and collarbone. A normal chest x-ray does not exclude the possibility of RSV bronchiolitis. M.C.'s chest x-ray results did not reveal any abnormalities, which supported a bronchiolitis diagnosis.

A lung ultrasound was not ordered for this patient. However, lung ultrasounds may be more effective than chest x-rays in diagnosing RSV bronchiolitis (Caiulo et al., 2011). Lung ultrasounds are more reliable than chest x-rays, can be done at the patient's bedside, and do not have the radiation risks of x-rays (Cauilo et al., 2011). Furthermore, lung ultrasounds may be better able to detect lung abnormalities associated with bronchiolitis than chest x-rays (Caiulo et al., 2011).

Treatments: Standards of Care Per Literature

Because RSV is caused by a virus, treatment for RSV is generally supportive. "Fever control and adequate fluid intake are the mainstays of treatment for RSV infected children being cared for at home. In children hospitalized for RSV infection, observation and supportive care are the primary treatments. These treatments include hydration; careful clinical assessment of respiratory status, including oxygen saturation, administration of supplemental oxygen as needed; suctioning of the upper airway; as well as intubation and mechanical ventilation when indicated. The patient should be placed on droplet isolation. Other therapies are available, but their benefit is limited and they generally are not recommended" (Todd et al., 2010).

Because her RSV- bronchiolitis was severe, but was not associated with possible comorbidities like pneumonia, M.C. received supportive care in the hospital environment. She received intravenous fluids in order to maintain hydration. M.C. was given oxygen therapy when her oxygen saturation levels suggested it was needed, though oxygen therapy was no longer required at the time of assessment. This was determined through oximetry, which is the process of assessing blood oxygen levels. Suction, which removes fluids and mucus from the body cavity, was also used to help maintain the integrity of M.C.'s airways.

Potential Long-Term Effects / Complications

Because there were no immediate complications for the RSV bronchiolitis, one might initially dismiss the possible long-term effects or complications of the illness. However, "RSV-related bronchiolitis severe enough to warrant hospitalization in infancy has been widely reported to be associated with later asthma, wheezing, and atopy" (Todd et al., 2010). This is not necessarily a cause-and-effect relationship. "How much these later problems are attributable to viral infection, or to genetic and environmental factors, or to an atopic predisposition is unclear" (Todd et al., 2010). Regardless of the cause, infant RSV is linked to "significantly more symptoms of wheezing disorder and clinical allergy than controls and were more likely to be sensitized to common inhaled allergens" (Todd et al., 2010). The number of studies and the number of subjects is still small, but the correlations have been consistently large enough to suggest that a serious bout of RSV-bronchiolitis in infancy is linked to later lung problems such as asthma, wheezing, and atopy. Therefore, M.C.'s parents should be educated about the possibility that M.C. may experience breathing problems in later life, and told to advise her primary care physician of her RSV diagnosis and hospitalization.