Path chap 5 + case studies

Chapter 5 Summary

• Age and sex-associated factors interact with genetic and environmental factors, lifestyle, and anatomical or hormonal differences to cause disease.

  • Men are more likely to experience diseases such as lung cancer, gout, and Parkinson's disease.

  • Women are more susceptible to osteoporosis, rheumatoid arthritis, and breast cancer.

• Analyzing disease risk includes considering:

  • Disease rates: incidence, prevalence, mortality

  • Disease risk factors: causal and noncausal

  • Interaction between risk factors, age, and sex differences is common.

• Genetic Risk:

  • A true genetic risk is inherited genetically through generations.

  • Familial tendency can occur without heritable gene abnormalities.

  • Autosomal Dominant Inheritance: One copy of a gene is sufficient to show the trait; a parent has a 50% chance of passing it to a child.

  • Autosomal Recessive Inheritance: Two copies of a gene are required to show the trait; a parent exhibiting the disease has a 50% chance of passing it on if the other parent does not.

• Immunologic Diseases:

  • Result from hyperactivity or hypoactivity of the immune system.

  • Allergies develop after initial exposure to allergens; repeated exposure leads to immune reactions.

  • Asthma: a chronic inflammatory condition with intermittent wheezing and mucus production.

  • Rheumatic Fever: develops from untreated streptococcal infections primarily affecting children.

• Cancer Overview:

  • General term for numerous malignant neoplasms; prognosis depends on tumor aggressiveness, spread, and treatment effectiveness.

  • Lung Cancer: Leading cause of cancer deaths; major risk factor is cigarette smoking.

  • Breast Cancer: Family history increases risk significantly; 5-10% may demonstrate autosomal dominant inheritance patterns.

  • Colorectal Cancer: Relatives have a higher risk of developing this disease.

• Diabetes Mellitus:

  • Two major forms: ketoacidosis-prone and non-ketoacidosis-prone, both inheriting predispositions.

• Hematologic Disorders:

  • Familial/genetic predispositions include: hemolytic anemia, hemophilia, hematochromatosis.

• Cardiovascular Disorders:

  • Specific inheritance patterns include autosomal dominant and recessive; familial tendencies observed in coronary heart disease, long QT syndrome, and stroke.

• Gout:

  • Caused by uric acid accumulation due to metabolic defect; related to genetics.

  • Kidney Stones: Can form in any part of the urinary system; often genetic-based.

• Malabsorption Disorders:

  • Result from bowel wall defects; include lactose intolerance, ulcerative colitis, Crohn's disease.

  • Peptic ulcers: Erosions in the GI tract not solely genetic; some familial patterns due to shared H. pylori infections.

• Gallstones:

  • Caused by bile substance precipitation; genetic factors account for 30% of symptomatic cases.

• Obesity:

  • Epidemic in the U.S.; genetic component likely but specific genes undetermined.

• Neuromuscular Disorders:

  • Include Huntington's disease, muscular dystrophy, multiple sclerosis, Alzheimer's disease, having familial components.

• Psychiatric Disorders:

  • Evidence supports familial and possibly genetic components in schizophrenia and manic-depressive disorders.

Case Study

Case Study, Part 1

• Scene Overview: 46-year-old man with abdominal pain in distress, pale, jaundiced, established by a nurse that he has liver cancer needing transport for evaluation.

• Patient Condition: Terminally ill, has type 2 diabetes, hepatitis C, and hemochromatosis.

• Initial Assessment:

  • V/S: Pulse 88 regular, BP 160/90 mm Hg, RR 20 nonlabored.

  • Questions:

    1. Causes of cancer? Multiple factors including genetic predisposition, environmental factors such as exposure to toxins, lifestyle choices (e.g., smoking), and infections (e.g., Hepatitis C).

    2. Are all medical problems related to cancer? Many chronic conditions can increase the risk of cancer; however, not all medical issues are directly associated with cancer.

    3. How is hemochromatosis inherited? Hemochromatosis is typically inherited in an autosomal recessive manner, requiring two copies of the defective gene for the disease to manifest.

Case Study, Part 2

• Symptoms: Unable to eat, significant weight loss.

• Physical Exam: Tender mass in right upper quadrant, normal lung sounds, visible jugular vein distention, low-grade fever.

• Diagnostic Tools: ECG shows normal sinus rhythm; blood glucose 99 mg/dL.

• Questions:

  1. Prognosis determination for cancer? Prognosis is determined based on several factors, including cancer type, stage, and the patient's overall health and response to treatment.

  2. Is liver cancer among leading cancer deaths? Liver cancer is among the leading causes of cancer deaths worldwide due to its often late diagnosis and aggressive nature.

Case Study, Part 3

• Ongoing Assessment: Symptoms of severe pain, tenderness, nausea, weakness, unchanged vital signs.

• Questions:

  1. Environmental factors contributing to cancer? Factors include exposure to carcinogens, pollution, lifestyle factors like diet and physical activity, and some infections.

  2. Type 2 diabetes hereditary? Type 2 diabetes has a genetic component, though it is strongly influenced by lifestyle and environmental factors too.

Case Study, Part 4

• Discussion: Phlebotomy treats hemochromatosis but does not prevent cancer development; not all patients with the disorder develop liver cancer…While phlebotomy can manage iron levels in hemochromatosis, it does not prevent the development of cancer, and not all individuals with the disorder will develop liver cancer.

Vital Vocabulary

• Allergen: Causes allergy.

• Alzheimer's Disease: Cortical atrophy and neuron loss.

• Asthma: Chronic inflammatory airway condition.

• Autosomal Dominant: One gene copy needed for the trait.

• Autosomal Recessive: Two copies needed to show the trait.

• Cardiomyopathy: Disease of the myocardium.

• Diabetes Mellitus: Metabolism disorder due to insulin lack.

• Gout: Uric acid accumulation in joints.

• Hemochromatosis: Iron overload disease.

• Lactose Intolerance: Inability to digest lactose.

• Peptic Ulcer Disease: Erosions in the GI tract lining.