Match List I with List II

Choose the correct answer from the options given below:

A-I, B-III, C-IV, D-II

The correct answer is option 4. A-I, B-III, C-IV, D-II.

A. \(A\) : (I) Night Blindness :

Night blindness is a visual impairment where a person has difficulty seeing in low light or dark conditions. It does not mean total blindness at night but rather reduced visual acuity in dim lighting. The primary cause of night blindness is a deficiency in vitamin A, though other conditions can also lead to this symptom. Here's how vitamin A deficiency affects vision:

Role of Vitamin A in Vision:

Rhodopsin Production: Vitamin A is essential for the synthesis of rhodopsin (also known as visual purple), a light-sensitive pigment found in the rod cells of the retina. Rhodopsin is crucial for night vision as it helps the eyes adapt to low-light conditions.

Retinal Health: Vitamin A also supports the health of the retina, which is responsible for converting light into neural signals that are sent to the brain.

Mechanism of Night Blindness:

Deficiency Impact: When there is insufficient vitamin A, the production of rhodopsin is impaired. This leads to reduced ability of the rod cells to function properly, making it difficult to see in low-light environments.

Symptoms: Individuals may experience poor vision in dim light, difficulty adjusting to darkness, and general visual impairment at night.

Diagnosis and Treatment:

Diagnosis:

Medical History and Symptoms: A healthcare provider will review symptoms and medical history, particularly dietary intake and any signs of deficiency.

Eye Examination: An eye exam may reveal signs of retinal damage or other visual issues related to vitamin A deficiency.

Treatment:

Vitamin A Supplementation: The primary treatment for night blindness caused by vitamin A deficiency is the intake of vitamin A supplements or increased dietary intake of vitamin A-rich foods (such as liver, carrots, sweet potatoes, and spinach).

Dietary Changes: Incorporating foods high in beta-carotene (which the body converts into vitamin A) can also be beneficial.

Addressing Underlying Conditions: If night blindness is due to another condition, such as retinitis pigmentosa or other retinal disorders, treatment will focus on managing that specific condition.

Prevention: Maintaining a diet rich in vitamin A and regular eye check-ups can help prevent night blindness related to nutrient deficiencies.

B. \(B_{12}\) : (III) Pernicious anaemia :

Pernicious anemia is a type of anemia that occurs due to a deficiency in vitamin \(B_{12}\). Pernicious anemia is an autoimmune disorder that results in a deficiency of vitamin \(B_{12}\), which is essential for red blood cell formation and neurological function.

Causes:

Autoimmune Destruction:

Intrinsic Factor: The primary cause of pernicious anemia is the body's immune system attacking and destroying the parietal cells in the stomach lining that produce intrinsic factor. Intrinsic factor is a protein essential for the absorption of vitamin \(B_{12}\) in the small intestine.

Absorption Issue: Without intrinsic factor, vitamin \(B_{12}\) cannot be properly absorbed from the diet, leading to a deficiency.

Vitamin \(B_{12}\) Deficiency: 

Dietary Insufficiency: In some cases, vitamin \(B_{12}\) deficiency can also be caused by a lack of vitamin \(B_{12}\) in the diet, though this is less common in pernicious anemia and more relevant to vegetarians and vegans who do not consume fortified foods or supplements.

Symptoms:

Hematologic Symptoms:

Anemia: Characterized by fatigue, weakness, pale skin, and shortness of breath due to a lack of red blood cells.

Macrocytic Anemia: Red blood cells become large and irregularly shaped.

Neurological Symptoms:

Numbness and Tingling: A common symptom is a "pins and needles" sensation in the hands and feet.

Balance and Coordination Issues: Difficulty walking, poor balance, and coordination problems.

Cognitive Changes: Memory problems and mood disturbances can also occur.

Gastrointestinal Symptoms:

Glossitis: Inflammation and soreness of the tongue.

Digestive Issues: Nausea and abdominal pain may also be present.

Diagnosis:

Blood Tests:

Vitamin \(B_{12}\) Levels: Blood tests will show low levels of vitamin \(B_{12}\).

Intrinsic Factor Antibodies: Testing for antibodies against intrinsic factor can confirm an autoimmune component.

Complete Blood Count (CBC): To check for anemia and the presence of macrocytic red blood cells.

Additional Tests:

Bone Marrow Biopsy: In some cases, a bone marrow biopsy may be performed to rule out other causes of anemia.

Treatment:

Vitamin \(B_{12}\) Supplementation:

Injections: High doses of vitamin \(B_{12}\) are typically administered via intramuscular injections to bypass the need for intrinsic factor.

Oral Supplements: In some cases, high-dose oral vitamin \(B_{12}\) supplements may be effective if absorption issues are less severe

Ongoing Management:

Regular Monitoring: Patients often need lifelong treatment and regular monitoring of vitamin \(B_{12}\) levels to prevent recurrence of anemia.

Prevention: 

There is no known way to prevent pernicious anemia since it is an autoimmune disorder. However, early diagnosis and treatment can manage symptoms and prevent complications.

C. \(C\) : (IV) Scurvy:

Scurvy is a disease resulting from a deficiency of vitamin C, also known as ascorbic acid. Vitamin C is an essential nutrient for humans because it plays a crucial role in the synthesis of collagen, a protein that is vital for the health and maintenance of connective tissues, such as skin, blood vessels, cartilage, and bones.

How Vitamin C Deficiency Leads to Scurvy:

Collagen Synthesis: Vitamin C is a cofactor for the enzymes prolyl hydroxylase and lysyl hydroxylase, which are necessary for the hydroxylation of proline and lysine amino acids in collagen. This hydroxylation is critical for stabilizing the collagen triple helix structure. Without sufficient vitamin C, collagen produced by the body is unstable and cannot maintain the integrity of connective tissues.

Symptoms of Scurvy:

Weakness and Fatigue: Due to impaired synthesis of collagen, tissues and blood vessels become weak, leading to general fatigue and malaise.

Swollen, Bleeding Gums: Collagen is essential for the health of gums and teeth. A lack of vitamin C results in gum inflammation, swelling, and bleeding, often leading to the loss of teeth in severe cases.

Petechiae and Purpura: Small blood vessels (capillaries) become fragile and rupture easily, leading to petechiae (small red spots caused by bleeding into the skin) and purpura (larger purple spots).

Poor Wound Healing: Wounds heal poorly or not at all because collagen is essential for tissue repair and regeneration.

Bone Pain and Weakness: Collagen is also a major component of bones. Without it, bones become weak and painful, often leading to fractures.

Prevention and Treatment:

Diet: Scurvy is easily prevented by consuming foods rich in vitamin C, such as citrus fruits (oranges, lemons), strawberries, kiwi, bell peppers, broccoli, and tomatoes.

Supplements: For those at risk or already suffering from scurvy, vitamin C supplements can effectively treat the condition. Typically, a dose of 100-200 mg of vitamin C per day is sufficient to cure scurvy in a matter of days to weeks.

Without adequate vitamin C, the body's ability to produce and maintain collagen diminishes, leading to the symptoms and complications associated with scurvy. However, with proper intake of vitamin C, scurvy is both preventable and treatable.

D. \(D\) : (II) Rickets:

Rickets is a disease that is primarily caused by a deficiency of vitamin D in the body. This condition affects bone development in children, leading to soft, weak bones that can result in deformities.

Explanation of Rickets:

Role of Vitamin D:

Calcium and Phosphorus Absorption: Vitamin D is crucial for the absorption of calcium and phosphorus from the intestines. These minerals are essential for the development and maintenance of healthy bones.

Bone Mineralization: Vitamin D helps regulate calcium and phosphate levels in the blood, which are necessary for proper bone mineralization. Without sufficient vitamin D, bones cannot properly mineralize, leading to soft and weak bones.

Symptoms of Rickets:

Bone Pain and Tenderness: Children with rickets often experience pain in their bones, particularly in the legs, pelvis, and spine.

Skeletal Deformities: Rickets can cause visible deformities in the bones, such as bowed legs or knock knees, and in severe cases, can lead to a curved spine (kyphosis or scoliosis).

Delayed Growth: A deficiency in vitamin D can impair normal growth, leading to shorter stature and delayed skeletal development.

Muscle Weakness: Rickets can also cause muscle weakness, which may make it difficult for children to walk or perform physical activities.

Prevention and Treatment:

Vitamin D Intake: The primary prevention of rickets involves ensuring adequate vitamin D intake through diet, sunlight exposure, and supplements if necessary. Foods rich in vitamin D include fatty fish (like salmon and tuna), fortified dairy products, and eggs.

Sunlight: Vitamin D is synthesized by the skin when exposed to sunlight, so regular sun exposure is important for preventing rickets.

Calcium: Adequate calcium intake is also necessary, as it works in conjunction with vitamin D to strengthen bones.

Treatment: Treatment of rickets typically involves increasing vitamin D and calcium intake through diet and supplements. In some cases, orthopedic surgery may be necessary to correct bone deformities.

Rickets is a preventable and treatable condition, but it can have serious consequences for bone health if left unaddressed. Ensuring adequate vitamin D and calcium intake is essential for preventing this disease, especially in growing children.