Nutrition and Metabolic Disorders Quiz

Nutrition

Definition: The presentation details Protein-Energy Malnutrition (PEM) as the condition arising from deficiency in macronutrients and certain micronutrients, leading to a lack of energy.
Geographical variations: PEM affects children in developing countries who lack adequate calories and protein. In contrast, developed countries see PEM affecting the older generation.
Classifications: PEM is categorized into primary and secondary PEM.
Types of Primary PEM: Children often experience primary PEM in two forms; Marasmus and Kwashiorkor.

Marasmus

Definition: Marasmus is a severe form of protein-energy malnutrition stemming from inadequate calorie intake.
Effects: Children with marasmus display significant growth retardation and substantial loss of muscle mass due to catabolism and depletion of somatic protein.
Adaptive Response: Body mobilizes muscle proteins and subcutaneous fat to utilize as energy—a vital adaptive mechanism.
Physical Appearance: A noticeable characteristic is emaciated extremities while the head typically appears disproportionately large in comparison to the body.

Etiology (PEM)

Children: Insufficient calorie intake, poverty, maternal education levels, and maternal illnesses like HIV/AIDS are critical factors in children.
Adults: Reduced food intake associated with age, physiological anorexia, depression, dementia, and elder abuse/neglect are contributing factors.

Pathophysiology (PEM)

Mechanism: Protein-energy deficiency leads to an inadequate adrenal cortex response, which results in an inhibited growth hormone response causing growth retardation.
Other effects: The diagram illustrates the disruption of normal plasma amino acid, normal lipoprotein, and muscle protein mobilization in the body.

Signs and Symptoms (PEM)

Physical: Dehydration symptoms are present, alongside significant weight loss that can be more apparent in the groin and armpit regions. Children are consistently below 60% of their expected weight for age group. Visible wasting associated with fat and muscle loss are significant markers. Prominent skeletal structure, aging faces, dry/loose and atrophied skin, brittle hair, and hair loss are common symptoms. Further symptoms often include lethargy, apathy, and weakness, alongside a BMI less than 16.
Specific Clinical Manifestations (PEM): Edema, bloated stomach with ascites, muscle wasting, skin lesions, dry brittle hair, fatty liver and stunted growth.

Complications (PEM)

Susceptibility to Infection: Prolonged calorie restriction affects T-cell function, reduces neutrophil activity, and causes atrophy of lymphoid tissues resulting in a severely compromised immune system.
Other effects: Electrolyte imbalances, fluid changes; total body water increase due to depleted protein stores; gastrointestinal changes like villous atrophy and enzyme loss; central nervous system and cognitive impairment; and cardiovascular adaptations, including reduced cardiac output, form part of the complication picture.

Diagnosis (PEM)

Physical Examination: Measurements of height/length of the body, upper-hand circumference, and assessment of height to age ratio are included.
Other Tests: Blood, stool, and urine samples further aid in the diagnosis process.

Treatment/Management (PEM)

Stages: Resuscitation and stabilization, nutritional rehabilitation, and follow-up and prevention of recurrence serve as the three stages in treatment.
Refeeding Syndrome: Children receiving treatment for marasmus are at risk; hence, nutritional rehabilitation must be carefully implemented and given slowly.

Kwashiorkor

Definition: Kwashiorkor is a condition of severe malnutrition marked by edema (swelling), resulting from a greater protein deficit than calorie deficit.
Geographic distribution: It's prominent in impoverished communities of Southeast Asia and Sub-Saharan Africa, typically affecting children between ages 1-5.
Causes (Etiology): Factors, such as weaning before sufficient protein development and infection, influence the pathogenesis of kwashiorkor.

Etiology (Goitre)

Iodine Deficiency: The most common cause is iodine deficiency in soil, water, and food; this typically occurs in mountainous regions.
Exposure to Goitrogens: Exposure to goitrogenic substances in food and/or water.
Chronic Auto-immune Thyroiditis: Inflammatory conditions affecting the thyroid gland.
Genetic Defects in Hormone Synthesis: Defects in hormonal production.

Goitre:Types

Two principal forms: Diffuse Non-toxic, and Multi-nodular.

Goitre:Diffuse Non-toxic

Known as simple goitre: Results from a non-nodular enlargement of the thyroid gland.
Characterized by generalized swelling.
Occurs in geographic regions with iodine deficiency—endemic areas, or in sporadic forms without a clear cause. Often presents in cases of puberty/young adult life.
Morphology: Two phases: Hyperplastic and Colloid involution phase; thyroid gland diffusely, and symmetrically enlarged; crowded follicle lining by columnar cells which may accumulate and form projections; not uniform over gland.

Goitre:Multinodular

Enlarged thyroid: Results from a nodular enlargement of the thyroid gland.
Commonly mistaken for tumors.
Develops from recurrent hyperplasia and involution.

Pathogenesis (Goitre)

Irregular shaped: Multinodular goiters exhibit irregularities in their shape, noticeably affecting one side more often than the other.
Location: Sometimes extends beneath the breastbone/collarbone area.

Morphology (Further details on goiter)

Microscopically: Colloid-rich follicles lined by flattened and inactive epithelium.
Other aspects: The appearance of areas exhibiting follicle hyperplasia (overgrowth) accompanied by degenerative changes that relate to physical stress (often inflammation).

Signs and Symptoms (Goitre)

Physical: Difficulty in swallowing, altered voice patterns (change of voice), hypothyroidism (cold sensitivity, weight gain), or hyperthyroidism (heat intolerance, weight loss); some discomfort or visible swelling at the front of the neck.

Diagnosis (Goitre)

Essential diagnostic procedures include imaging techniques, lab tests, and clinical examinations.

Treatment (Goitre)

Essential approaches: Monitoring goitre growth, surgical intervention options, iodine supplementation, and hormone replacement therapy in cases of hormone deficiency are important steps in treatment.

Hemochromatosis

Definition: A genetic condition characterized by iron overload in the body. Primarily affects the liver, pancreas, heart, and other organs.
Form: An autosomal recessive disease that typically manifests in adulthood.
Cause (Etiology): Mutations in the HFE gene lead to excessive iron absorption.

Pathophysiology (Hemochromatosis)

Mechanism: Excessive intestinal iron absorption leads to iron overload, depositing in organs.
Effects: This overload can damage various organs, including the liver, heart, pancreas, liver fibrosis, cardiomyopathy, and tissue deposition.

Morphology (Hemochromatosis)

Microscopically: Liver exhibiting characteristic coarse yellow-gold iron granules of hemosiderin distributed within cytoplasm.
Further aspects: The presence of Prussian blue stain highlights these iron granules.
Macroscopic: Diagram shows the liver in various states, from normal to cirrhotic and instances exhibiting hepatocellular carcinoma (HCC).

Signs and Symptoms/Complications (Hemochromatosis)

Common presentation: Symptoms commonly arise in organs with the highest iron concentration, like the liver (liver disease), skin involvement (bronzing/hyperpigmentation), diabetes, and cardiomyopathy.
Stages: Iron overload typically needs to reach high levels before observable symptoms occur, which can impact an individual's quality of life substantially.

Diagnosis (Hemochromatosis)

Key diagnostic steps include measurements of serum iron and ferritin levels, exclusion of other causes of iron overload (secondary), and when necessary, obtaining liver biopsies, as well as screening of relatives/family members to assess underlying mutations.

Treatment (Hemochromatosis)

Key objective: To reduce/lower body iron levels.
Method: Treatments, such as phlebotomy or iron chelators, effectively manage excess iron. Patients who receive early diagnosis and effective treatment can lead a relatively normal life expectancy.
Dietary Management: Following a healthy diet, avoiding iron-rich foods and vitamin-C supplements, and monitoring all secondary manifestations (e.g., diabetes, cardiomyopathy) are crucial steps to maintaining well-being.

Gout

Definition: A form of inflammatory arthritis caused by high uric acid levels leading to the precipitation of monosodium urate crystals in joints.
Etiology: Two main contributing factors are overproduction of uric acid (due to genetic anomalies in enzyme activity or excessive purine intake) and impaired uric acid excretion (due to genetic predispositions or conditions impacting kidneys' ability to remove uric acid). Additional metabolic factors such alcohol consumption and certain medications (e.g., diuretics, aspirin, etc.) also play a role in the pathogenesis of this condition.

Pathophysiology (Gout)

Sequence of events: Initial high levels of uric acid, which precipitate as monosodium urate crystals; these crystals deposit in joints, soft tissues, and kidneys. Immune response kicks in.
Immune response: Macrophages and immune cells recognize crystals through NLRP3 activation and release of pro-inflammatory cytokines. This prompts other inflammatory cells (neutrophils) to arrive.
Repeated attacks: Repeated inflammatory flares lead to chronic joint damage resulting in deformity. Tophi formation and chronic synovitis are also part of the clinical presentation.

Signs and Symptoms (Gout)

Primary presenting characteristics: Intense joint pain; lingering discomfort; inflammation/redness; joint warmth; palpable tenderness; limited range of motion; tophi formation.

Diagnosis (Gout)

Physical examination: Inspecting and assessing symptoms, including joint inflammation.
Imaging: X-rays, ultrasound, and advanced modalities like CT scans (specifically dual-energy CT) and MRI scans aid in the examination of affected joints.
Laboratory tests: Blood tests, specifically those for uric acid levels and other markers. Joint aspiration—removal of fluid from the affected joint—is an additional diagnostic tool.

Treatment (Gout)

Acute management: Focuses on relieving acute pain and inflammation. Typically includes NSAIDs, colchicine, and corticosteroids.
Long-term management: Lowering uric acid levels. This usually involves medications such as allopurinol and febuxostat.
Lifestyle changes: Includes adopting a dietary low-purine diet (reducing alcohol and high-purine foods), and potentially modification of other factors (managing underlying metabolic conditions, adjusting/stopping medications that increase uric acid levels, and weight loss or maintenance).