Nutritional requirements and disorders

Nutritional requirements and disorders US Medical PG Question 1: A 61-year-old woman presents for a routine health visit. She complains of generalized fatigue and lethargy on most days of the week for the past 4 months. She has no significant past medical history and is not taking any medications. She denies any history of smoking or recreational drug use but states that she drinks "socially" approx. 6 nights a week. She says she also enjoys a "nightcap," which is 1–2 glasses of wine before bed every night. The patient is afebrile, and her vital signs are within normal limits. On physical examination, there is significant pallor of the mucous membranes. Laboratory findings are significant for a mean corpuscular volume (MCV) of 72 fL, leukocyte count of 4,800/mL, hemoglobin of 11.0 g/dL, and platelet count of 611,000/mL. Stool guaiac test is negative. She is started on oral ferrous sulfate supplements. On follow-up, her laboratory parameters show no interval change in her MCV or platelet level, and she reports good compliance with the medication. Which of the following is the best next step in the management of this patient?

• A. Transfuse the patient with whole blood
• B. Administer folate
• C. Administer iron intravenously (Correct Answer)
• D. Continue oral ferrous sulfate and supplement with omeprazole
• E. Continue oral ferrous sulfate and supplement with ascorbic acid

Nutritional requirements and disorders Explanation: **Administer iron intravenously** - The patient shows **microcytic anemia** (MCV 72 fL) and **thrombocytosis** (platelet count 611,000/mL), which are classic signs of **iron deficiency anemia**. - Given the failure of oral ferrous sulfate to improve her parameters, despite likely good adherence given the repeat visit, **intravenous iron** is the next appropriate step to ensure adequate iron repletion. *Transfuse the patient with whole blood* - **Blood transfusion** is reserved for patients with severe, symptomatic anemia, often with a hemoglobin level much lower than 11.0 g/dL, or in cases of acute hemorrhage. - This patient's anemia is chronic and her hemoglobin level, while low, is not critically low enough to warrant immediate transfusion. *Administer folate* - **Folate deficiency** typically causes **macrocytic anemia** (high MCV), not microcytic anemia, making it an inappropriate treatment for this patient. - Though chronic alcohol use can affect folate levels, the patient's presentation is more consistent with iron deficiency. *Continue oral ferrous sulfate and supplement with omeprazole* - **Omeprazole** is a **proton pump inhibitor** that can actually *reduce* iron absorption by decreasing gastric acidity, making it counterproductive in treating iron deficiency. - Continuing oral iron alone was already proven ineffective, necessitating a more aggressive approach. *Continue oral ferrous sulfate and supplement with ascorbic acid* - **Ascorbic acid (vitamin C)** can enhance the absorption of non-heme iron; however, since the initial trial of oral ferrous sulfate alone was ineffective, merely adding ascorbic acid may not be sufficient. - The lack of improvement suggests either poor absorption or significant ongoing loss, which intravenous iron addresses more directly.

Nutritional requirements and disorders US Medical PG Question 2: A 5-month-old boy is brought to the pediatrician by his parents, who began noticing that the infant was not able to hold his head upright when sitting or in a prone position. Upon examination, the infant has a musty odor, fair skin with patches of eczema, and blue eyes. The pediatrician orders laboratory tests and prescribes a special diet. Which of the following amino acids becomes essential and must be supplemented in this patient's condition?

• A. Thiamine
• B. Large neutral amino acids
• C. Arginine
• D. Phenylalanine-free amino acid formula
• E. Tyrosine (Correct Answer)

Nutritional requirements and disorders Explanation: ***Tyrosine*** - This patient presents with **phenylketonuria (PKU)**, characterized by the classic triad of developmental delay, musty odor (from phenylketones in urine), and hypopigmentation (fair skin, blue eyes, eczema). - PKU is caused by **phenylalanine hydroxylase deficiency**, which prevents the conversion of phenylalanine to tyrosine. - Because tyrosine cannot be synthesized from phenylalanine, **tyrosine becomes a conditionally essential amino acid** in PKU patients and must be supplemented in the diet. - Treatment consists of a phenylalanine-restricted diet with **tyrosine supplementation** to ensure adequate protein synthesis and melanin production. *Arginine* - Arginine becomes conditionally essential in **urea cycle disorders**, where it helps drive nitrogen excretion. - However, this patient's presentation (musty odor, hypopigmentation, eczema) is classic for PKU, not a urea cycle disorder. - Urea cycle disorders typically present with hyperammonemia, vomiting, lethargy, and encephalopathy—not the findings described here. *Phenylalanine-free amino acid formula* - This is a **dietary intervention**, not an amino acid that becomes essential. - While phenylalanine-free formulas are crucial in PKU management, the question specifically asks which amino acid becomes essential and must be supplemented. - Phenylalanine itself is *restricted*, not supplemented. *Thiamine* - Thiamine (vitamin B1) is a **vitamin**, not an amino acid. - It is a cofactor for enzymes in carbohydrate metabolism and is deficient in beriberi and Wernicke-Korsakoff syndrome. - It is not relevant to PKU management. *Large neutral amino acids* - Large neutral amino acids (LNAAs) can be used as an **adjunctive therapy** in PKU to compete with phenylalanine for transport across the blood-brain barrier. - However, they are not the amino acid that becomes conditionally essential due to the metabolic block. - The primary nutritional requirement is **tyrosine supplementation** to replace what cannot be synthesized.

Nutritional requirements and disorders US Medical PG Question 3: A 1-year-old male presents to his pediatrician for a well-child visit. Through a history from the mother and physical examination, the pediatrician learns that the baby babbles non-specifically, takes several steps independently, and picks up his cereal using two fingers. His weight is currently 22 lbs (birth-weight 6 lbs, 9 oz), and his height is 30 inches (birth length 18 inches). Are there any aspects of this child's development that are delayed?

• A. Fine motor skill delay
• B. Language delay (Correct Answer)
• C. Inadequate growth
• D. Gross motor skill delay
• E. There are no developmental concerns

Nutritional requirements and disorders Explanation: ***Language delay*** - At 1 year of age, a child should typically be babbling with **specific sounds** and attempting to say their **first words**. - The child's non-specific babbling suggests a delay in typical **expressive language development**. *Fine motor skill delay* - The child is able to pick up cereal using **two fingers**, indicating the development of a **pincer grasp**. - This is an **age-appropriate fine motor skill** for a 1-year-old. *Inadequate growth* - The child has over **tripled his birth weight** (from 6 lbs, 9 oz to 22 lbs) and more than doubled his birth length (from 18 to 30 inches), which are **normal growth patterns** for the first year of life. - While weight values can be plotted on growth charts, the provided information strongly suggests **adequate growth**. *Gross motor skill delay* - The child is taking **several steps independently**, which is an **age-appropriate gross motor milestone** for a 1-year-old. - Many children take their first independent steps between 9 and 15 months. *There are no developmental concerns* - While many milestones are met, the **non-specific babbling** at 1 year strongly suggests a **language delay**. - It is crucial to identify and address any potential delays early for intervention.

Nutritional requirements and disorders US Medical PG Question 4: A 12-month-old boy presents with pallor, fatigue, and conjunctival pallor. Examination reveals a grade II systolic ejection murmur. Labs show: Leukocytes 6,500/mm^3, Hemoglobin 6.4 g/dL, Platelets 300,000/mm^3, MCV 71 µm^3, Reticulocytes 2.0%, Serum iron 34 mcg/dL, Ferritin 6 ng/mL (normal 7-140 ng/mL), TIBC 565 mcg/dL (normal 240-450 mcg/dL). Peripheral smear shows microcytosis and hypochromia. In addition to starting iron supplementation, what dietary modification is most important to address the underlying cause?

• A. Administer deferoxamine
• B. Limit milk intake (Correct Answer)
• C. Echocardiogram
• D. Measure lead level
• E. Iron supplementation

Nutritional requirements and disorders Explanation: ***Limit milk intake*** - The patient's presentation and lab results (low Hb, low MCV, low ferritin, high TIBC) are highly indicative of **iron deficiency anemia**. Excessive cow's milk intake (typically >24 oz/day) in infants is a leading cause of iron deficiency through multiple mechanisms: displacing iron-rich foods from the diet, causing occult gastrointestinal blood loss, and impairing iron absorption due to calcium content. - With severe anemia (Hb 6.4 g/dL), **iron supplementation is essential** and should be started immediately (3-6 mg/kg/day elemental iron). However, addressing the underlying **dietary cause** by limiting milk to 16-24 oz/day and encouraging iron-rich foods (meat, fortified cereals) is crucial to prevent recurrence and ensure long-term resolution. - This question tests understanding of the **etiology** of nutritional iron deficiency in toddlers, where excessive milk consumption is the most common preventable cause. *Administer deferoxamine* - **Deferoxamine** is a chelating agent used to treat **iron overload** (hemochromatosis, transfusional iron overload, acute iron poisoning). - This patient has severe iron **deficiency**, so removing iron would be harmful and contraindicated. *Echocardiogram* - An **echocardiogram** evaluates cardiac structure and function, indicated for suspected structural heart disease or pathologic murmurs. - The grade II systolic ejection murmur is likely a **flow murmur** from high cardiac output due to severe anemia. Once anemia is corrected, the murmur should resolve. Echocardiogram is not the priority and would only be considered if the murmur persists after anemia correction. *Measure lead level* - **Lead poisoning** can cause microcytic anemia and should be considered in at-risk children. - However, lead poisoning typically shows **normal or elevated ferritin** (lead causes anemia of chronic disease plus iron dysregulation), whereas this patient has **very low ferritin (6 ng/mL)** and **markedly elevated TIBC (565)**, which are classic for iron deficiency, not lead toxicity. *Iron supplementation* - **Iron supplementation is absolutely necessary** for this patient with severe anemia (Hb 6.4 g/dL) and should be started immediately along with dietary counseling. - However, the question specifically asks for the dietary modification needed **in addition to** iron supplementation to address the **underlying cause**. Without limiting excessive milk intake, iron deficiency will likely recur even with supplementation.

Nutritional requirements and disorders US Medical PG Question 5: A 55-year-old woman presents with fatigue. She says her symptoms are present throughout the day and gradually started 4 months ago. Her past medical history is significant for rheumatoid arthritis–treated with methotrexate, and diabetes mellitus type 2–treated with metformin. The patient is afebrile, and her vital signs are within normal limits. A physical examination reveals pallor of the mucous membranes. Initial laboratory tests show hemoglobin of 7.9 g/dL, hematocrit of 22%, and mean corpuscular volume of 79 fL. Which of the following is the best next diagnostic step in this patient?

• A. Serum ferritin level and total iron-binding capacity (TIBC)
• B. Serum ferritin and serum iron levels
• C. Serum ferritin and soluble transferrin receptor levels (Correct Answer)
• D. Serum iron level
• E. Serum ferritin level

Nutritional requirements and disorders Explanation: ***Serum ferritin and soluble transferrin receptor levels*** - This patient has **anemia** (hemoglobin 7.9 g/dL) with **microcytic** (MCV 79 fL) and **hypochromic** features, suggesting either **iron deficiency anemia (IDA)** or **anemia of chronic disease (ACD)**. Given her history of **rheumatoid arthritis**, ACD is highly likely, but co-existing IDA needs to be excluded. - **Serum ferritin** is an acute-phase reactant, so it can be elevated in ACD masking a co-existing iron deficiency. **Soluble transferrin receptor (sTfR)** levels are increased in IDA and remain normal or only mildly elevated in ACD, making it a reliable marker to differentiate between these two conditions when ferritin is uninterpretable due to inflammation. *Serum ferritin level and total iron-binding capacity (TIBC)* - While these tests are useful for diagnosing iron deficiency, **ferritin** can be falsely elevated in the context of inflammation (e.g., from **rheumatoid arthritis**), making it unreliable for diagnosing IDA in this patient. - **TIBC** can be decreased in ACD, complicating its interpretation for IDA when inflammation is present. *Serum ferritin and serum iron levels* - As mentioned, **serum ferritin** is an acute-phase reactant and may be elevated due to **rheumatoid arthritis**, potentially masking **iron deficiency**. - **Serum iron levels** fluctuate significantly and are not a reliable standalone indicator for iron status, especially in the context of chronic disease. *Serum iron level* - **Serum iron levels** are highly variable and not sufficient for diagnosing **iron deficiency** or differentiating it from **anemia of chronic disease**. - A low serum iron can be seen in both IDA and ACD but does not provide definitive diagnostic information on its own. *Serum ferritin level* - Measuring **serum ferritin** alone is insufficient because it is an **acute-phase reactant** that can be elevated due to the patient's **rheumatoid arthritis**, even if she has co-existing **iron deficiency anemia**. - A normal or high ferritin level in this context does not rule out **iron deficiency**.

Nutritional requirements and disorders US Medical PG Question 6: A 70-year-old male presents to his primary care physician for complaints of fatigue. The patient reports feeling tired during the day over the past 6 months. Past medical history is significant for moderately controlled type II diabetes. Family history is unremarkable. Thyroid stimulating hormone and testosterone levels are within normal limits. Complete blood cell count reveals the following: WBC 5.0, hemoglobin 9.0, hematocrit 27.0, and platelets 350. Mean corpuscular volume is 76. Iron studies demonstrate a ferritin of 15 ng/ml (nl 30-300). Of the following, which is the next best step?

• A. Blood transfusion
• B. MRI abdomen
• C. CT abdomen
• D. Colonoscopy (Correct Answer)
• E. Gel electrophoresis

Nutritional requirements and disorders Explanation: ***Colonoscopy*** - The patient presents with **fatigue** and **microcytic anemia** (hemoglobin 9.0, MCV 76), coupled with **low ferritin** (15 ng/ml), indicating **iron deficiency anemia**. - In a 70-year-old male, **iron deficiency anemia** is a strong indicator of **gastrointestinal blood loss** (often occult), and colonoscopy is the most appropriate next step to investigate for potential causes like **colorectal cancer** or polyps. - Standard evaluation typically includes **bidirectional endoscopy** (both upper and lower GI), but colonoscopy is prioritized in elderly males due to high risk of **colorectal malignancy**. *Blood transfusion* - While the patient's hemoglobin is low, there are no signs of **hemodynamic instability** or severe symptoms requiring immediate transfusion. - Transfusing blood addresses the symptom (anemia) but does not identify or treat the **underlying cause** of the iron deficiency. *MRI abdomen* - An MRI of the abdomen is not the primary diagnostic tool for investigating the source of **GI blood loss** in iron deficiency anemia. - It would be considered if other imaging or endoscopic procedures were inconclusive, or if specific **soft tissue abnormalities** were suspected. *CT abdomen* - A CT scan of the abdomen may identify large masses but is less sensitive than colonoscopy for detecting mucosal lesions, polyps, or early malignancies, which are common causes of **occult GI bleeding**. - It also involves **radiation exposure** and is not the initial investigation of choice for suspected lower GI bleeding. *Gel electrophoresis* - Gel electrophoresis (e.g., hemoglobin electrophoresis) is used to diagnose **hemoglobinopathies** like **thalassemia** or **sickle cell disease**. - Given the patient's **low ferritin** and **microcytic anemia**, iron deficiency is the most likely diagnosis, making electrophoresis an inappropriate next step.

Nutritional requirements and disorders US Medical PG Question 7: A 5-year-old boy presents to the pediatrician for a well child visit. He is meeting his developmental milestones and is in the 15th percentile for height and 70th percentile for weight. His parents report that he complains of fatiguing easily and having trouble participating in sports. They are concerned he is not getting enough sleep and state that sometimes they hear him snore. The patient has a past medical history of a supracondylar fracture of the humerus, which was appropriately treated. He is doing well in school but is sometimes bullied for being small. The patient eats a balanced diet of milk, fruit, and some vegetables. His parents have been trying to get him to drink more milk so he can grow taller. His temperature is 99.5°F (37.5°C), blood pressure is 90/48 mmHg, pulse is 100/min, respirations are 19/min, and oxygen saturation is 98% on room air. On physical exam, the patient appears well. HEENT exam is notable for conjunctival pallor and a unilateral clear middle ear effusion. Cardiac exam reveals a benign flow murmur. Pulmonary exam is clear to auscultation bilaterally. The patient's gait is stable and he is able to jump up and down. A full set of labs are ordered as requested by the parents including a serum vitamin D level, B12 level, and IGF level. A selection of these lab values are seen below. Serum: Na+: 139 mEq/L Cl-: 100 mEq/L K+: 4.3 mEq/L HCO3-: 25 mEq/L BUN: 20 mg/dL Glucose: 99 mg/dL Creatinine: 1.1 mg/dL Ca2+: 9.9 mg/dL AST: 12 U/L ALT: 10 U/L Which of the following would you expect to find in this patient?

• A. Decreased IGF levels
• B. Increased RDW and TIBC (Correct Answer)
• C. Decreased oxygen saturation when the patient sleeps
• D. Increased MCV
• E. Decreased vitamin D level

Nutritional requirements and disorders Explanation: ***Increased RDW and TIBC*** - The patient presents with **conjunctival pallor**, fatigue, and snoring, falling in the 15th percentile for height and 70th for weight, suggesting **iron deficiency anemia**. Anemia would cause an **increased red cell distribution width (RDW)** as red blood cells vary in size, and **increased total iron-binding capacity (TIBC)** as the body tries to maximize iron absorption. - While other signs of mild anemia like glossitis or pica are not explicitly mentioned, the combination of symptoms and the common prevalence of **iron-deficiency anemia** in children due to inadequate dietary intake or rapid growth phases supports this finding. Prolonged milk intake can inhibit iron absorption. *Decreased IGF levels* - **Insulin-like growth factor (IGF) levels** are primarily associated with growth hormone deficiency or severe malnutrition, which is not strongly indicated here. The patient's height is at the 15th percentile, which is *small*, but within the normal range, and his weight is at the 70th percentile, indicating he is not severely malnourished. - While fatigue and small stature can be associated with growth disorders, the overall presentation with pallor points more distinctly towards an alternative diagnosis like **anemia** rather than growth hormone axis dysfunction. *Decreased oxygen saturation when the patient sleeps* - The patient's snoring could suggest **sleep-disordered breathing** or **sleep apnea**, leading to decreased oxygen saturation during sleep. - However, based on the *conjunctival pallor*, fatigue, and growth concerns, **iron deficiency anemia** is a more prominent diagnosis, and while sleep apnea is possible, direct evidence of desaturation is not provided. *Increased MCV* - An **increased MCV (macrocytic anemia)** is characteristic of deficiencies in **vitamin B12** or **folate**. - The patient's symptoms, particularly conjunctival pallor and fatigue, are more consistent with a **microcytic anemia** (decreased MCV), often caused by **iron deficiency**, rather than a macrocytic one. *Decreased vitamin D level* - While **fatigue** can be a symptom of **vitamin D deficiency**, the more prominent findings of **conjunctival pallor** and height/weight percentiles are less directly indicative of this specific deficiency as the primary diagnosis. - The patient's diet includes milk and fruit, which are typically fortified or contain vitamin D, making a severe deficiency less likely to be the primary cause of his symptoms, though a mild deficiency cannot be ruled out without specific lab results.

Nutritional requirements and disorders US Medical PG Question 8: An 11-month-old boy presents with the recent loss of appetite and inability to gain weight. His diet consists mainly of cow’s milk and fruits. Family history is unremarkable. Physical examination shows conjunctival pallor. Laboratory findings are significant for the following: Hemoglobin 9.1 g/dL Mean corpuscular volume 75 μm3 Mean corpuscular hemoglobin 20 pg/cell Red cell distribution width 18% The patient is presumptively diagnosed with iron deficiency anemia (IDA) and ferrous sulfate syrup is prescribed. Which of the following laboratory values would most likely change 1st in response to this treatment?

• A. ↓ Mentzer index
• B. ↑ mean corpuscular hemoglobin
• C. ↑ reticulocyte count (Correct Answer)
• D. Normalization of hemoglobin
• E. ↓ Anisocytosis

Nutritional requirements and disorders Explanation: ***↑ reticulocyte count*** - An increase in the **reticulocyte count** is the earliest sign of a bone marrow response to iron supplementation. Reticulocytes are immature red blood cells, and their production rapidly increases as the bone marrow utilizes available iron to make new healthy red blood cells. - This typically occurs within **3-7 days** of initiating iron therapy, reflecting effective erythropoiesis before changes in hemoglobin or other red cell indices become apparent. *↓ Mentzer index* - The **Mentzer index** is used to differentiate between iron deficiency anemia and thalassemia trait; it is not a direct measure of treatment response. - A low Mentzer index (MCV/RBC count < 13) suggests thalassemia, while a high index (MCV/RBC count > 13) suggests iron deficiency. This value would not be the first to change post-treatment. *↑ mean corpuscular hemoglobin* - **Mean corpuscular hemoglobin (MCH)** reflects the average amount of hemoglobin in a single red blood cell. While it will eventually increase with successful treatment, this change occurs after the reticulocyte count elevation. - MCH improvement signifies the production of fully hemoglobinized red blood cells, which takes longer than the initial surge in immature red cell release. *Normalization of hemoglobin* - **Hemoglobin levels** will gradually rise and normalize with effective iron therapy, typically over several weeks to months. - This is a later indicator of treatment success, occurring after the initial reticulocytosis. *↓ Anisocytosis* - **Anisocytosis** refers to variation in red blood cell size, measured by **red cell distribution width (RDW)**. In iron deficiency anemia, RDW is typically elevated. - While RDW will eventually decrease as the red blood cell population becomes more uniform with treatment, this change is not the earliest response. The initial production of new red cells can even temporarily increase RDW before it normalizes.

Nutritional requirements and disorders US Medical PG Question 9: A 28-year-old gravida 1 para 1 woman is being seen in the hospital for breast tenderness. She reports that both breasts are swollen and tender. She is also having difficulty getting her newborn to latch. The patient gave birth 4 days ago by uncomplicated vaginal delivery. During her pregnancy, the patient developed gestational diabetes but was otherwise healthy. She took folate and insulin. She attended all her pre-natal appointments. Upon examination, the patient has a low grade fever, but all other vital signs are stable. Bilateral breasts appear engorged and are tender to palpation. There is no erythema, warmth, or induration. A lactation nurse is brought in to assist the patient and her newborn with more effective breastfeeding positions. The patient says a neighbor told her that breastmilk actually lacks in nutrients, and she asks what the best option is for the health of her newborn. Which of the following components is breastmilk a poor source of?

• A. Whey protein
• B. Vitamin D (Correct Answer)
• C. Lysozymes
• D. Phosphorus
• E. Immunoglobulin A

Nutritional requirements and disorders Explanation: ***Vitamin D*** - **Breast milk** is naturally a **poor source of vitamin D**, making supplementation necessary for breastfed infants to prevent **rickets** and ensure adequate bone development. - While small amounts of vitamin D are present, they are often insufficient to meet the infant's requirements, especially if maternal vitamin D levels are also low. *Whey protein* - **Whey protein** is a major component of breast milk, contributing to its digestibility and providing essential **amino acids** for infant growth. - It is specifically rich in **alpha-lactalbumin**, which has both nutritional and antimicrobial properties. *Lysozymes* - **Lysozymes** are abundant in breast milk and play a crucial role in the infant's innate **immune defense** by breaking down bacterial cell walls. - These enzymes help protect against gastrointestinal infections and contribute to the establishment of healthy gut flora. *Phosphorus* - **Phosphorus** is an essential mineral found in sufficient quantities in **breast milk**, crucial for **bone mineralization**, energy metabolism, and cell function. - Its concentration is carefully regulated to meet the needs of the growing infant without overloading immature kidneys. *Immunoglobulin A* - **Secretory IgA (sIgA)** is the predominant **immunoglobulin** in breast milk, providing passive immunity by coating the infant's intestinal tract and preventing pathogen attachment. - It is crucial for protecting the infant from various infections, especially those affecting the gastrointestinal and respiratory systems.

Nutritional requirements and disorders US Medical PG Question 10: A 5-month-old male presents to the pediatrician with his mother for a well visit. The patient was born at 35 weeks gestation to a 30-year-old gravida 2 via vaginal delivery. The pregnancy and labor were uncomplicated. The patient required no resuscitation after delivery and was discharged from the hospital on day two of life. His mother now reports that the patient has been exclusively breastfed since birth, and she says that feedings have been going well, and that the patient appears satisfied afterwards. The patient feeds for 30 minutes every two hours and urinates 8-10 times per day. The patient’s mother reports that she eats a varied diet that includes animal products, but she worries that the patient is not meeting his nutritional needs with breastmilk alone. The patient’s height and weight at birth were in the 15th and 20th percentile, respectively. His height and weight are now in the 20th and 25th percentile, respectively. His temperature is 98.1°F (36.7°C), blood pressure is 58/46 mmHg, pulse is 128/min, and respirations are 34/min. On physical exam, the patient appears well-developed and well-nourished. He has mild conjunctival pallor. Which of the following is the most appropriate guidance regarding this patient’s nutritional needs?

• A. Add cow's milk to his diet
• B. Supplement his diet with formula
• C. No changes are necessary to his diet
• D. Supplement his diet with iron and vitamin D (Correct Answer)
• E. Add pureed foods to his diet

Nutritional requirements and disorders Explanation: ***Supplement his diet with iron and vitamin D*** - This 5-month-old infant, exclusively breastfed, requires **iron supplementation** because maternal iron stores are depleted by 4-6 months, and breast milk is a poor source of iron. Additionally, **Vitamin D supplementation** is crucial for all exclusively breastfed infants to prevent rickets. - The presence of mild **conjunctival pallor** further suggests possible iron deficiency. *Add cow's milk to his diet* - **Cow's milk** should not be introduced before 12 months of age as it contains high protein and mineral content that can stress an infant's immature kidneys and can lead to **gastrointestinal bleeding**, insufficient iron absorption, and **iron-deficiency anemia**. - It also has a low iron content and lacks the essential fatty acids necessary for proper infant development. *Supplement his diet with formula* - While formula contains iron and vitamin D, the mother reports that the baby is feeding well and appears satisfied, with appropriate weight gain (20th to 25th percentile) and frequent wet diapers, indicating **adequate nutrition from breast milk alone**. - **Exclusive breastfeeding** is recommended for the first 6 months of life when feasible, and there is no clear indication that breast milk alone is insufficient for overall caloric and macronutrient needs here yet. *No changes are necessary to his diet* - This is incorrect because, despite adequate breastfeeding, **exclusive breastfed infants** like this one require supplementation with **iron and vitamin D** to meet their micronutrient needs. - The mild conjunctival pallor also suggests a potential, or impending, deficiency that warrants intervention. *Add pureed foods to his diet* - The current recommendations suggest introducing solid foods, including pureed foods, around **6 months of age**, when the infant shows signs of developmental readiness. - While the infant is close to 6 months, introducing solids at 5 months is typically not necessary if growth is appropriate and specific micronutrient deficiencies (like iron and vitamin D) can be addressed through supplementation.

Nutritional requirements and disorders Flashcard 1 of 8

Question: What is the most common cause of iron deficiency in infants? _____

Answer: Breastfeeding (human milk is low in iron)

Nutritional requirements and disorders Flashcard 2 of 8

Question: Celiac disease in _____ (age group) classically presents as abdominal distention, steatorrhea, and failure to thrive

Answer: children

Nutritional requirements and disorders Flashcard 3 of 8

Question: By what age can a toddler feed themselves with fork/spoon?_____

Answer: 20 months

Nutritional requirements and disorders Flashcard 4 of 8

Question: Carbamoyl phosphate synthetase I deficiency presents in _____ (age group) as poorly regulated respiration and body temperature, poor feeding, developmental delay, and intellectual disability

Answer: neonates

Nutritional requirements and disorders Flashcard 5 of 8

Question: What malnutrition disorder presents as a small child with a swollen abdomen? _____

Answer: Kwashiorkor

Nutritional requirements and disorders Flashcard 6 of 8

Question: sleep enuresis

Answer:

Extra Information: desmopressin (DDAVP), imipramine; desmopressin preferred because of fewer adverse effects

Nutritional requirements and disorders Flashcard 7 of 8

Question: marasmus

Answer: energy malnutrition

Extra Information: muscle wasting, loss of subcutaneous fat, +/- edema

Nutritional requirements and disorders Flashcard 8 of 8

Question: kwashiorkor

Answer: protein malnutrition

Extra Information: skin lesions, edema, liver malfunctionanemia, fatty liver