5.1 Flashcards
(13 cards)
- How is ‘disease’ defined in the context of pathology?
Disease is defined as an abnormality in the function or structure of body organs and systems. It represents a disruption of normal physiological processes.
- What is pathology, and why is it fundamental to medicine?
Pathology is the study of disease, encompassing the causes (aetiology), the sequence of events leading to disease (pathogenesis), and the structural changes (morphology) that occur in tissues. It is fundamental because understanding disease at a cellular and molecular level underpins diagnosis, treatment, and prevention.
- What does the term ‘lesion’ refer to in a clinical and pathological context?
A lesion is an area of abnormal tissue, which may be identified through clinical examination or imaging, and represents a localized change that can be linked to a specific disease process.
- How is ‘aetiology’ defined, and what are its common causes?
Aetiology refers to the initiating cause of a disease, which can include genetic factors, environmental exposures, infections, or lifestyle factors. It answers the question of ‘why’ a disease develops.
- What is meant by ‘pathogenesis’ in the study of disease?
Pathogenesis is the sequence of molecular, biochemical, and cellular events that lead from the initial cause (aetiology) to the development and progression of disease. It explains the ‘how’ of disease evolution.
- How is ‘morphology’ used in the context of diagnosing disease?
Morphology refers to the structural alterations seen in cells or tissues that are characteristic of a specific disease. These changes, which can be observed microscopically or macroscopically, often serve as diagnostic clues to the underlying aetiologic process.
- What role do clinical manifestations play in the study and diagnosis of disease?
Clinical manifestations are the symptoms and signs that result from the underlying genetic, biochemical, and structural alterations in a disease. They provide the observable outcome of the disease process and guide clinical management and prognosis.
- What are some common approaches to classifying disease?
Various classification systems exist to organize diseases – for example, classifying them as congenital versus acquired, infectious versus non-communicable, genetic versus environmental, neoplastic versus non-neoplastic, or systemic versus organ-specific. The WHO International Classification of Diseases (ICD) is widely used for standardization and statistical purposes.
- What are some limitations of disease classification systems like the ICD?
While the ICD offers global standardization, its broad categories may oversimplify complex disease processes, lead to overlap between categories (e.g., immune and infectious disorders both involve inflammation), and fail to capture multifactorial etiologies or the nuances of pathogenesis.
- How can a systematic approach be applied when assessing a lesion or disease process?
A systematic approach involves first identifying the lesion, then determining its aetiology (cause), describing the pathogenesis (sequence of events leading to the lesion), and characterizing its morphology (structural changes). Finally, the clinical manifestations are correlated with these findings to establish a diagnosis.
- How does a structured evaluation of a lesion benefit clinical diagnosis?
By breaking down the evaluation into discrete components—such as aetiology, pathogenesis, morphology, and clinical presentation—clinicians can more accurately pinpoint the underlying cause, distinguish between overlapping disease categories, and tailor treatment based on a comprehensive understanding of the disease process.
- Using the case of bacterial pneumonia as an example, how are the concepts of aetiology, pathogenesis, and morphology integrated in clinical assessment?
In bacterial pneumonia, the aetiology is a bacterial infection (e.g., Streptococcus pneumoniae). The pathogenesis involves exposure, predisposition (such as an elderly, compromised immune system), bacterial proliferation, and an acute inflammatory response. Morphologically, affected lung tissue shows consolidation with alveoli filled with neutrophils and bacterial colonies. This systematic assessment, coupled with clinical manifestations like cough and shortness of breath, leads to an accurate diagnosis.
