A Proper understanding of the pathophysiology of diseases and conditions is essential in their treatment as well as management. Every disease has a way of affecting the normal functioning of the body. Some disorders attack the whole body while others affect specific organs. Therefore, it is crucial to study the pathophysiology of diseases. It is also essential to understand the relationship between related diseases. This helps in understanding the interactions between the diseases. This paper is set to examine the pathophysiology of pneumonia, hypoxemia, as well as thyroid cancer. Additionally, the paper analyses the relationship between these diseases.
Pathophysiology of Pneumonia
Pneumonia refers to an infectious process that leads to invasion and excessive growth of microorganisms in the parenchyma of the lungs (Munjal & Sharm, 2012). This attack results in the breakdown of body defences provoking exudation of intra-alveoli fluids. Various types of pneumonia exist. The common types include nosocomial pneumonia as well as community pneumonia. Nosocomial pneumonia refers to a type of the disease acquired within a hospital setting. It develops approximately forty-eight hours following hospital admission (Munjal & Sharm, 2012). Community pneumonia is acquired by an individual who has little or no contact with the health care setting.
The severity and development of pneumonia depend on the balance between the host and pathogenic factors. Some of the pathogenic factors affecting the severity of pneumonia include inoculum size and virulence of the pathogen. Microorganisms present in the upper sections of the airways move to the lower parts by micro-aspiration. However, both acquired and innate mechanisms of defence by the lungs usually keep these areas sterile. Patients with impaired immune systems are commonly susceptible to pneumonia infections. The impairments in the immune systems can be as a result of HIV/AIDS infection or ageing.
When the lungs are affected, the capillaries become leaky resulting into the seeping of fluid into the lung alveoli. The seepage reduces the functional area for carbon dioxide as well as oxygen exchange. Due to reduced exchange of oxygen as well as carbon dioxide, the patient becomes deficient of oxygen. The accumulation of carbon dioxide in the lungs makes the patient breathe faster. The production of mucus increases with increase in the leaking of the vessels (Farrar, Hotez, Junghanss, Kang, Lalloo, & White, 2013). The mucus may be tinged with blood from the capillaries. The mucus plugs also decrease the gas exchange efficiency within the alveoli. The leakage of blood results into the filling of the alveoli with blood and debris from the destroyed white blood cells. The white blood cells are produced to fight the infection.
The alveoli can become hard due to the debris and fluid within them. This consolidation further affects the exchange of gases (Riccabona, 2012). Consolidation is common in bacterial pneumonia. Mycoplasma and Viral pneumonia do not lead to consolidation. The two types of pneumonia affect the lung's parenchyma and alveoli walls. The alveoli are usually with fluids such as blood, inhaled water, inflammatory exudates, as well as pulmonary oedema. Pulmonary consolidation must be present for the diagnosis of pneumonia.
Pathophysiology of Hypoxemia
Hypoxemia is a condition resulting from oxygen level that is below the average amount (Munjal & Sharm, 2012). It is often regarded as a sign of underlying breathing problem. The disease can be determined by measuring the level of oxygen in the arteries. Besides, a pulse oximeter can be used in measuring the saturation of blood. It is a tiny device that is clipped to the finger to detect blood flow in the arteries. In normal circumstances, arterial oxygen should be approximately seventy-five to one hundred millimetres of mercury (Farrar et al., 2013). Any value below sixty millimetres of mercury is often regarded as low and could lead to hypoxemia.
Most pathophysiologic mechanisms resulting into hypoxemia in various diseases include shunt and V/Q mismatch. The two mechanisms results into the widening of the arterial-alveoli potential of oxygen (PO2) gradient. This value is usually less than 15 mmHg (Munjal & Sharm, 2012). The mechanisms can be differentiated through the assessment of the response to supplementation of oxygen as well as the calculation of shunt fraction following inhalation of one hundred percent oxygen inhalation. The V/Q (Ventilation-perfusion) mismatch is regarded as the primary cause of hypoxemia. The reduction in the V/Q values may result into hypercapnia or hypoxemia. When 100% oxygen is administered, the low V/Q ratios are often eliminated leading to the correction of the condition.
When hypoxemic condition persists despite inhalation of 100% oxygen, shunt usually occurs. The shunt is a condition because there is adequate perfusion of blood into the alveoli and subsequent failure of the blood to supply air to the perfused region. In pulmonary shunt, the alveoli are adequately filled with blood but fail to participate in the gaseous exchange with the blood vessels (Munjal & Sharm, 2012). The deoxygenated blood mixes with oxygenated blood that has by-passed the ventilated alveoli. This passage and mixing reduce the blood content of the arteries. Apart from pneumonia, shunt also causes atelectasis and cardiac or non-cardiac oedema. It is challenging to correct hypoxemia that results from shunt by administration of oxygen.
Pathophysiology of Thyroid Cancer
The pathophysiology of the condition is yet to be completely defined. However, alterations in some molecular factors are believed to contribute to the development and spread of thyroid malignancy. These factors include oncogenes, growth hormones, as well as tumour receptors. A combination of these proliferative and inhibitory factors are characterised by increased risk of thyroid cancers (Riccabona, 2012). Physiological behaviours of the cells and organs depend on the type of tumour. Patients with thyroid cancers experience increased grading, differentiation of the tumours, as well as loss of specific functions of the thyroid gland such as accumulation of iodine.
Thyroid cancer is regarded as one of the highly vascular tumours. Vascular endothelial growth factor (VEGF) is a major molecular mediator that results in the vascularization of the tumours. In thyroid cancer, the VEGF is highly expressed compared to the normal thyroid tissues (Riccabona, 2012). The level of VEGF is higher in patients with thyroid malignancies compared to individuals with natural thyroids. Therefore, the VEGF has been implicated in the development and spread of thyroid malignancies.
The Relationship between Pneumonia, Hypoxemia and Thyroid Cancer
There is a relationship that exists between pneumonia, hypoxemia, as well as thyroid organs. However, these relationships are complex and not direct. These relationships can only be derived by the determination of the relationship between two conditions (Munjal & Sharm, 2012). For instance, it is possible to determine the relationship between pneumonia and hypoxemia or hypoxemia and thyroid cancer. The direct determination of the relationship between hypoxemia, pneumonia, and thyroid cancer offer numerous challenges.
There has been an increase in the number of children with pneumonia who develop hypoxic conditions. These hypoxemic conditions usually occur in patients with severe pneumonia. These conditions have been recognised as some of the most lethal complications of pneumonia. The prevalence of pneumonia patients with hypoxemia varies from one geographical area to the other. However, they are often common in the developing countries. Approximately 13.3% of pneumonia cases are hypoxemic (Salah et al., 2015).
Hypoxemic conditions lead to the elevation of the level of oestrogen in the blood. Oestrogen is believed to affect the functions as well as the growth of thyroid gland. An increase in serum oestrogen leads to vascularization of the thyroid tumours, which lead to their growth (Munjal & Sharm, 2012). Since the thyroid tumours are more frequent in women than men, it is believed that oestrogen has a role to play in thyroid cancers. When surgeries are conducted to correct the malignancies, oestrogen is usually detected. The presence of oestrogen in these tumours has been linked to its role in the malignancies.
Some patients with thyroid carcinomas often develop metastases. Most of these metastases regularly occur in the thoracic cavity. When these metastases occur within the parenchyma of the lungs, they can lead to pulmonary infiltrations as well as pleural infusions (Riccabona, 2012). Metastases that reach the lungs are often associated with respiratory conditions such as dyspnea. These metastases move into the alveoli leading to infection of these air sacs.
The pathophysiology of diseases is essential in the treatment as well as management of conditions. Understanding the pathophysiology and relationship between diseases or conditions is important in the field of medical sciences. Besides, it enables individuals to understand the interactions of the diseases within the body cells as well as organs.
References
Farrar, J., Hotez, P., Junghanss, T., Kang, G., Lalloo, D., & White, N. J. (2013). Manson's tropical diseases. Amsterdam: Elsevier Health Sciences.
Munjal, Y. P., & Sharm, S. K. (2012). API Textbook of Medicine, Two Volume Set. London: JP Medical Ltd.
Riccabona, G. (2012). Thyroid cancer: its epidemiology, clinical features, and treatment. Berlin: Springer Science & Business Media.
Salah, E. T., Algasim, S. H., Mhamoud, A. S., & Husian, N. (2015). Prevalence of hypoxemia in under-five children with pneumonia in an emergency pediatrics hospital in Sudan. Indian journal of critical care medicine: peer-reviewed, official publication of Indian Society of Critical Care Medicine, 19(4), 203.
