GenPath: (9) Environmental and Nutritional Diseases

In an epidemiologic study of individuals whose BMI is greater than 35, data on lifestyle and disease patterns are collected. Investigators observe that a subset of obese individuals has a consistently high caloric intake because they lack a feeling of satiety when eating. These individuals have diminished responsiveness of a hypothalamic receptor for which of the following molecules? A. Adenosine B. Glucagon C. Glucose D. Insulin E. Leptin

E

Ingested ethanol is observed to be metabolized by alcohol dehydrogenase to an intermediate compound that, upon further metabolism, depletes reduced nicotinamide adenine dinucleotide (NAD+) in the cytoplasm of hepatocytes. Fatty acid oxidation is subsequently reduced. Population studies show some persons have deficient enzyme activity to metabolize this intermediate compound. What is this intermediate compound? A. Acetaldehyde B. α-Tocopherol C. Formic acid D. Glutathione E. Hydrogen peroxide

A

A 26-year-old woman has had amenorrhea for the past 8 years. She fractured her right wrist 1 year ago after a minor fall to the ground. On physical examination, she is 175 cm (5 ft 7 in) tall and weighs 52 kg (BMI 17). She has normal secondary sex characteristics. There are no abnormal findings. Radiographic measurement of bone density by dual-energy x-ray absorptiometry shows a bone mineral density that is 1.5 standard deviations below the young adult reference range. Laboratory findings include anemia and hypoalbuminemia. Which of the following is the most likely diagnosis? A. Anorexia nervosa B. Bulimia C. Kwashiorkor D. Rickets E. Scurvy

A

A 26-year-old woman with a 6-month history of depression accompanied by active suicidal ideation ingests 35 g of acetaminophen. She quickly experiences nausea and vomiting. Within 1 day, she becomes progressively obtunded. On physical examination, her temperature is 36.9° C, pulse is 75/min, respirations are 15/min, and blood pressure is 100/65 mm Hg. She is treated with N-acetylcysteine. Depletion of which of the following is most likely to accentuate her organ damage? A. Glutathione (GSH) B. Amylase C. Creatine kinase D. Ketone bodies E. Potassium

A

A 5-year-old boy is brought to the physician for examination. A police agency suspects child abuse. On physical examination, the child's skin has the appearance shown in the figure. Which of the following terms best describes this injury? A. Abrasion B. Contusion C. Hypothermia D. Kwashiorkor E. Laceration F. Thermal burn

A

A 7-year-old boy falls off his bicycle while riding down the street at 5 km/hr. The skin of his right calf and right arm scrape along the pavement, and the top layer of epidermis is removed. Which of the following terms best describes this injury? A. Abrasion B. Burn C. Contusion D. Incision E. Laceration

A

A 75-year-old woman lives alone and eats sparingly because of her low fixed retirement income. For the past 2 weeks, she has noticed pain in her right leg. On physical examination, there is marked tenderness to palpation over the lateral aspect of the right shin, a poorly healed cut on the right hand, and a diffuse hyperkeratotic skin rash. A radiograph shows a right tibial diaphyseal subperiosteal hematoma. Laboratory studies show a hemoglobin level of 11.3 g/dL. A deficiency of which of the following nutrients is most likely to explain these findings? A. Ascorbic acid B. Folate C. Niacin D. Riboflavin E. Vitamin A F. Vitamin K

A

An epidemiologic study observes increased numbers of respiratory tract infections among children living in a community in which most families are at the poverty level. The infectious agents include Streptococcus pneumoniae, Haemophilus influenzae, and Klebsiella pneumoniae. Most of the children have had pneumonitis and rubeola infection. The study documents increased rates of keratomalacia, urinary tract calculi, and generalized papular dermatosis in these children as they reach adulthood. These children are most likely to have a deficiency of which of the following vitamins? A. Vitamin A B. Vitamin B1 C. Vitamin E D. Vitamin D E. Vitamin K

A

An epidemiologic study of a community shows an increased incidence for basal cell and squamous cell carcinomas in adults. These lesions are distributed predominantly on palms and soles. Analysis of groundwater pumped from wells for drinking shows increased levels of a heavy metal used in pressure-treated lumber (with a greenish hue), insecticides, and herbicides. Which of the following metals is most likely implicated by this study? A. Arsenic B. Beryllium C. Cadmium D. Lead E. Mercury

A

In a study of lifestyle influences on health, investigators observe that sending children outside to play instead of letting them sit for hours in front of the television can have long-term health benefits. Which of the following tissues is most likely to be in better condition by middle age from this lifestyle change? A. Bone fractures B. Ocular cataracts C. Urinary tract calculi D. Pulmonary emphysema E. Skin cancers

A

A 55-year-old woman has been steadily gaining weight for the past 30 years. She underwent a cholecystectomy for cholelithiasis 5 years ago. She does not smoke. She is now 164 cm (5 ft 4 in) tall and weighs 126 kg (BMI 47). On physical examination, she has decreased range of motion with pain on movement of the knees. Laboratory studies show a serum glucose level of 176 mg/dL. This patient is at greatest risk of developing which of the following neoplasms? A. Colonic adenocarcinoma B. Endometrial carcinoma C. Hepatocellular carcinoma D. Pulmonary adenocarcinoma E. Renal cell carcinoma

B

A 33-year-old man incurs thermal burn injuries to 40% of his total body surface area in an accidental fire while repairing a fuel storage tank. On physical examination, the skin of the trunk, neck, and face is pink, shows blister formation, and is painful when touched. The skin of the arms is white and anesthetic. Skin grafting is necessary on the arms, but not on other injured areas of skin. Which of the following tissue components, when absent, will necessitate skin grafting? A. Collagen fibers B. Dermal appendages C. Epidermal stratum spinosum D. Keratin E. Macrophages F. Nerve endings

B

A 5-year-old child has had recurrent upper respiratory infections for the past 2 months. The child is at the 55th percentile for height and the 38th percentile for weight. Physical examination shows generalized edema, ascites, muscle wasting, and areas of desquamating skin over the trunk and extremities. Laboratory studies are most likely to show which of the following findings? A. Abetalipoproteinemia B. Hypoalbuminemia C. Hypocalcemia D. Hyperglycemia E. Megaloblastic anemia

B

A 63-year-old man with a history of chronic arthritis has had pronounced tinnitus and episodes of dizziness for the past 6 months. He has had a headache and nausea for the past 2 days. Physical examination shows he is afebrile but has a respiratory rate of 35/min and heart rate of 100/ min. He has scattered petechiae over the skin of the upper extremities. There is no apparent bone conduction or nerve hearing loss. A stool guaiac test result is positive. Laboratory studies show serum lactate is 6 mmol/L. An arterial blood gas analysis shows a pH of 7.25; Po2, 95 mm Hg; Pco2, 35 mm Hg; and HCO3 -, 15 mEq/L. Acute and chronic toxicity from which of the following drugs best explains these findings? A. Acetaminophen B. Aspirin C. Chlorpromazine D. Iron E. Morphine F. Quinidine G. Tetracycline

B

A 72-year-old man has had increasing dyspnea for the past year. Decreased breath sounds are heard on auscultation of the right side of the chest. A chest radiograph shows a large pleural mass that nearly encases the right lung. Exposure to which of the following metals is most likely to be associated with these findings? A. Arsenic B. Asbestos C. Beryllium D. Chromium E. Nickel

B

A 75-year-old man who lives alone in a poorly ventilated house without central heating uses a portable unvented kerosene heater to warm the house during the winter months. One morning, a neighbor finds him in an obtunded state. On physical examination, he appears cyanotic. Results of blood gas measurement on room air are Po2, 90 mm Hg; Pco2, 35 mm Hg; and pH, 7.3. Pulse oximetry shows low oxygen saturation. Exposure to which of the following is most likely to have produced this man's illness? A. Beryllium B. Carbon monoxide C. Nitrous oxide compounds D. Oxygen E. Ozone F. Sulfur dioxide

B

A clinical study of adults with a body mass index of at least 30 is undertaken. About 8% of these individuals do not have hyperphagia, but are found to have normal levels of leptin and ghrelin, along with a diminished basal metabolic rate. A mutation in which of the following genes is most likely present in these individuals? A. OB-R B. MC4R C. OB D. POMC E. PPARγ

B

A poorly funded epidemiologic study is conducted, and the results appear in a publication available at the supermarket checkout counter. The study analyzes the diet of textbook authors. Which of the following is determined to be the most likely dietary deficiency in this population? A. Calcium B. Chocolate C. Folate D. Iron E. Vitamin C

B

An 8-year-old girl exhibits lethargy and somnolence with dizziness and weakness after a 6-hour bus ride returning from a week at summer camp. On physical examination, her temperature is 37° C, pulse is 107/min, respiratory rate is 28/ min, and blood pressure is 130/85 mm Hg. Breath sounds are audible in all lung fields with no wheezes or crackles. Arterial blood gas analysis shows pH, 7.35; Po2, 95 mm Hg; Pco2, 37 mm Hg; and HCO3 - 20 mEq/L. Pulse oximetry shows an oxygen saturation of 90%, but the spectrophotometrically measured oxyhemoglobin saturation is 60%. Her blood lactic acid is 8 mmol/L, and total creatine kinase is 445 U/L. She is given 100% oxygen in a hyperbaric chamber and improves in 20 minutes. She is most likely to have experienced poisoning with which of the following? A. Aspirin (acetylsalicylic acid) B. Carbon monoxide C. Iron sulfate D. Lead E. Methanol F. Organophosphate insecticide

B

An epidemiologic study evaluates the rate of dental caries and tooth abscesses among children living in communities within a metropolitan area. Investigators discover that the rate is high among children living in an upper middle class community, but low in children living in a community below the poverty level. The levels of trace elements in the water supplies for those communities are measured. A higher level of which of the following minerals in the water is most likely to be associated with a lower rate of dental decay among the children living in the poor community? A. Copper B. Fluoride C. Iodine D. Selenium E. Zinc

B

During a qualifying match for the World Cup, the goalkeeper is hit in the chest by a soccer ball (football) kicked from 10 m away. He stays in the game. Which of the following injury patterns is most likely to be seen over the chest of the goalkeeper? A. Abrasion B. Contusion C. Incision D. Laceration E. Puncture

B

In an experiment, the effects of xenobiotic activation of the compound benzo[a]pyrene, a chemical carcinogen present in cigarette smoke, are studied in various tissues. Investigators determine that formation of a secondary metabolite, which binds covalently to DNA, increases the frequency of lung cancers. Genetic polymorphisms are found among persons that affect this frequency. Which of the following is the most likely metabolic pathway for generation of this xenobiotic? A. Biomethylation B. Cytochrome P-450 C. Flavin-containing monooxygenase D. Glucuronidation E. Glutathione reduction F. Peroxidase-dependent cooxidation

B

The firemen who initially responded to fight the fires from the Chernobyl nuclear reactor accident were exposed to high radiation levels. Some of the men received doses exceeding 50 Sv (5000 cGy). Within hours, many became extremely ill. Damage to which of the following tissues most likely led to this finding? A. Bone marrow B. Cerebrum C. Heart D. Lungs E. Small intestine

B

While attending a party, a 19-year-old university student drinks 2 L of mixed alcoholic beverages containing 50% ethanol by volume over 30 minutes. He usually does not drink much alcohol. His major use of drugs consists of acetaminophen for headaches. Which of the following complications is most likely to prove lethal within the first 12 hours? A. Acute pancreatitis B. Brainstem depression C. Hepatic cirrhosis D. Variceal bleeding E. Wernicke disease

B

While touring the grounds of the Imperial Palace in Kyoto, a 75-year-old woman collapses suddenly. She remains conscious, but says that she feels weak and light headed. On physical examination by the nurse, her temperature is 35.2° C, pulse is 93/min, respirations are 17/min, and blood pressure is 95/50 mm Hg. The temperature in the shade is 34° C with 90% humidity. One hour after drinking cool green tea, the woman revives and is able to return to her hotel. Which of the following terms best describes these findings? A. Heat cramps B. Heat exhaustion C. Heat stroke D. Malignant hyperthermia E. Thermal inhalation injury

B

Increasing numbers of children younger than 5 years are observed to exhibit cerebral palsy, deafness, blindness, and mental retardation in a coastal community. A coal-burning power plant was built in this community 5 years ago. Affected families have a high consumption of seafood. Which of the following compounds ingested during pregnancy by the mothers of these children is most likely to be responsible for the illness affecting the children? A. Bisphenol A B. Cadmium C. Methyl mercury D. Organochlorine E. Vinyl chloride

C

"It was terribly cold and nearly dark on the last evening of the old year, and the snow was falling fast. In the cold and the darkness, a poor little girl, with bare head and naked feet, roamed through the streets. So the little girl went on with her little naked feet, which were quite red and blue with the cold. Shivering with cold and hunger, she crept along." Which of the following pathologic findings in soft tissues is most likely to be present in this girl? A. Acute inflammation B. Apoptosis C. Edema D. Hemorrhage E. Nuclear karyorrhexis

C

5 It is 1:00 am and a hard-working second-year medical student is intent on finishing her pathology reading assignment. Soon she begins to note that her concentration is fading because 7 hours have passed since she had dinner, and she is feeling famished. Having studied the chapter on ischemic heart disease, she decides to be prudent and forgoes her favorite chocolate cookies, and instead devours two apples, gulping them down with a glass of low-fat milk. Of the following substances, which one was most likely to have increased rapidly when she became hungry and decreased promptly after she finished her healthy snack? A. α-MSH B. Corticotropin-releasing factor (CRF) C. Ghrelin D. Leptin E. Thyrotropin-releasing hormone (TRH)

C

A 14-year-old boy was taken to the emergency department of a local hospital, where he died 2 hours later. The principal finding on examination is shown in the figure. Laboratory studies showed that the hematocrit was 17%. Which of the following terms best describes this injury? A. Blast injury B. Electrocution injury C. Gunshot wound D. Incised wound E. Laceration

C

A 27-year-old, previously healthy man suddenly collapses at a party where both legal and illicit drugs are being used. En route to the hospital, he requires resuscitation with defibrillation to establish a normal cardiac rhythm. On physical examination, his temperature is 40° C; respirations, 30/ min; heart rate, 110/min; and blood pressure, 175/90 mm Hg. He has dilated pupils, a perforated nasal septum, and a prominent callus on the right thumb. CT scan of the head shows an acute right frontal lobe hemorrhage. Which of the following substances is most likely responsible for these findings? A. Amphetamine B. Barbiturate C. Cocaine D. Ethanol E. Heroin F. Marijuana G. Phencyclidine

C

A 3-year-old boy does not appear to be developing normally. On physical examination, the child has the appearance shown in the figure. The results from vision testing are normal. There are no petechiae or areas of purpura on the skin. The abdomen is not enlarged. Which of the following is the most likely diagnosis? A. Beriberi B. Kwashiorkor C. Rickets D. Pellagra E. Scurvy

C

A 40-year-old man notes a family history of colon carcinoma. He asks his physician how best to reduce his risk of developing this type of cancer. Which of the following dietary practices should he be advised to follow each day? A. Consume more beef B. Drink a glass of red wine C. Eat more vegetables D. Have a bowl of ice cream E. Reduce intake of chocolate

C

A 76-year-old man has noticed a gradually enlarging nodule on the right lower eyelid for 3 years. On physical examination, the 0.8-cm umbilicated nodule is firm and has a small central area of ulceration. The nodule is excised, and plastic repair to the eyelid is performed. Which of the following forms of radiation most likely played the greatest role in the development of this man's lesion? A. Gamma rays B. Infrared rays C. Ultraviolet rays D. Visible rays E. X-rays

C

A case-control study of adult men and women is performed to determine the relationship between obesity and cancer. The data indicate an increased risk for cancers of the esophagus and kidney in subjects with a body mass index above 25. Which of the following substances is most likely to contribute to the development of cancer in these subjects? A. Adiponectin B. Aflatoxin C. Insulin-like growth factor 1 (IGF-1) D. Leptin E. Selenium F. Trans fats

C

A textbook author standing knee-deep in a rising tide next to his home notes that this phenomenon is becoming more frequent. He surmises that the risk for illnesses from infections in populations living in such coastal areas is increasing. Which of the following is most likely to be affected by illness in these populations? A. Cardiovascular system B. Central nervous system C. Gastrointestinal tract D. Hematopoietic system E. Respiratory tract F. Urinary tract

C

An 18-year-old pregnant woman receives no prenatal care, eats a diet containing mostly carbohydrates and fats, and does not take prenatal vitamins with iron. She feels increasingly tired and weak during the third trimester. The infant is born at 35 weeks' gestation and is listless during the first week of life. Laboratory studies show markedly decreased serum ferritin levels in the infant and the mother. Which of the following findings from a nutritional deficiency is most likely to be present in both the infant and the mother? A. Dermatitis B. Diffuse goiter C. Microcytic anemia D. Peripheral neuropathy E. Skeletal deformities F. Soft tissue hemorrhages

C

Several children between the ages of 3 and 6 years have been admitted to a local hospital because of encephalopathic crisis. They have lived in the same community all their lives. All have previously exhibited retarded psychomotor development. On physical examination, the children have diffuse abdominal pain and are experiencing nausea and vomiting. Head CT scans show marked cerebral edema. Laboratory studies show microcytic anemia. An investigator sent to the housing project where the children live finds a rundown apartment complex with extensive water damage, poor plumbing and ventilation. Toxic exposure to which of the following substances best accounts for these findings? A. Ethylene glycol B. Kerosene C. Lead D. Methanol E. Sodium hypochlorite

C

A 20-year-old man is brought to the hospital emergency department by a friend who found him unconscious in his apartment after trying to contact him for 3 days. On arrival, the patient is in a state of respiratory depression. He experiences convulsions for 2 minutes, followed by cardiac arrest. Advanced cardiac life support measures are instituted, and he is stabilized and intubated. On physical examination, there are needle tracks in the left antecubital fossa, miosis, and a loud diastolic heart murmur. His temperature is 39.2° C. Use of which of the following substances by this man most likely produced these findings? A. Cocaine B. Ethanol C. Flurazepam D. Heroin E. Meperidine F. Phencyclidine G. Lysergic acid

D

A 22-year-old star football player suddenly collapses during practice and has a cardiac arrest and cannot be resuscitated. The medical examiner investigating this sudden death finds marked coronary atherosclerosis and histologic evidence of hypertension in the renal blood vessels at autopsy. Use of which of the following substances by this man most likely led to these findings? A. Amphetamine B. Barbiturate C. Benzodiazepine D. Cocaine E. Ethanol F. Heroin G. Marijuana

D

A 3-year-old child has erosion of a roughened corneal surface caused by xerophthalmia. Keratomalacia results in corneal scarring with eventual blindness after 4 years. This ocular damage is now less common because of a United Nations initiative to treat a dietary deficiency of which of the following nutrients? A. Iron B. Niacin C. Protein D. Vitamin A E. Vitamin K

D

A 45-year-old man, whose mother, father, brother, and uncle all had a history of heart disease, asks his physician about ways to reduce his risk of developing coronary artery disease. The patient is 171 cm (5 ft 6 in) tall, weighs 91 kg, and has a blood pressure of 125/80 mm Hg. His blood glucose concentration is 181 mg/dL. Which of the following is the best dietary advice to give this patient? A. Avoid adding salt to food B. Drink more water C. Increase dietary fiber D. Reduce intake of saturated fat E. Take vitamin A supplements

D

A 48-year-old woman injured her right wrist in a fall down a flight of stairs. On physical examination, she has marked pain on palpation of the wrist and does not want to move the hand. A radiograph of the right hand and arm shows marked osteopenia and a fracture of the radial head. Which of the following underlying diseases is most likely to contribute to the risk of fracture in this patient? A. Atrophic gastritis B. Chronic lymphocytic leukemia C. Coronary atherosclerosis D. Primary biliary cirrhosis E. Pulmonary emphysema

D

A clinical trial involves patients with a diagnosis of cancer who have intractable nausea as a result of chemotherapy. The patients are divided into two groups; the group receiving the drug is found to have reduced self-reported nausea and diminished weight loss compared with the placebo group. The patients receiving the drug seem to have no major adverse side effects. Of the following agents, classified as drugs of abuse in parts of the world, which is most likely to have the beneficial effects found in this study? A. Barbiturate B. Cocaine C. Heroin D. Marijuana E. Methylphenidate F. Methamphetamine G. Phencyclidine

D

An environmental study shows that a gas that exists in nature is present at increased levels in polluted city air. In the upper atmosphere, this gas blocks harmful ultraviolet radiation. At ground level, this gas generates free radicals in the lower respiratory tract. What is this gas? A. Argon B. Carbon dioxide C. Nitrogen dioxide D. Ozone E. Sulfur dioxide

D

An infant born at term has Apgar scores of 8 and 9 at 1 and 5 minutes. The infant appears healthy, but 3 days after birth, there is bleeding from the umbilical cord stump, and ecchymoses are observed over the buttocks. Seizures soon develop. Which of the following nutrients is most likely deficient in this infant? A. Folic acid B. Iodine C. Iron D. Vitamin E E. Vitamin K

E

A 61-year-old woman living in a city with very poor air quality has developed a worsening cough over the past 7 months. She has an 80 pack-year history of smoking cigarettes. One week ago she had an episode of hemoptysis. A chest radiograph shows a 7-cm infiltrative, perihilar mass in the right lung. Exposure to which of the following airborne agents is most likely to be associated with these findings? A. Carbon monoxide B. Nicotine C. Nitrous oxide compounds D. Ozone E. Polycyclic aromatic hydrocarbons F. Dusts containing silica G. Sulfur dioxide

E

A case-control study seeks to identify long-term effects of hormone replacement therapy (HRT) in postmenopausal women receiving exogenous estrogens coupled with progestins compared with a control group not receiving this therapy. The medical records of the women in the study are reviewed after 20 years. Which of the following complications is most likely to be observed in the women receiving HRT? A. Cervical carcinoma B. Chronic ulcerative colitis C. Hepatic cirrhosis D. Pulmonary emphysema E. Thromboembolism

E

A previously healthy, 27-year-old agricultural worker develops nausea, vomiting, abdominal cramps, cough with wheezing and dyspnea, salivation, and lacrimation 1 hour after leaving work in a field. On examination, he is afebrile with a heart rate of 50/min and blood pressure of 90/55 mm Hg. Laboratory studies show plasma cholinesterase activity less than 50% of normal. Atropine is given intravenously, and his condition improves. He was most likely exposed to which of the following substances? A. Aflatoxin B. Cyclodiene C. Dioxin D. Ergot alkaloid E. Organophosphate F. Pyrethrin

E

A 20-year-old man is trying to repair an old electrical appliance in his garage. While testing the function of the appliance, his right hand comes in contact with a frayed electrical cord carrying 120-V, 10-amp alternating current. Which of the following is most likely to develop as a consequence of this electrical injury? A. Bronchoconstriction B. Cerebral artery thrombosis C. Heat stroke D. Gastric hemorrhage E. Ventricular fibrillation

E

A 3-year-old boy has had a succession of respiratory infections during the past 6 months. On physical examination, the child appears chronically ill, listless, and underdeveloped. He is 50% of ideal body weight and has marked muscle wasting. Laboratory findings include hemoglobin, 9.4 g/dL; hematocrit, 27.9%; MCV, 75 μm3; platelet count, 182,000/mm3; WBC count, 6730/mm3; serum albumin, 4.1 g/dL; total protein, 6.8 g/dL; glucose, 52 mg/dL; and creatinine, 0.3 mg/dL. Which of the following is most likely to explain these findings? A. Bulimia B. Folate deficiency C. Kwashiorkor D. Lead poisoning E. Marasmus

E

A 30-year-old woman is found dead in her hotel room 3 hours after firemen extinguish a fire on the floor below. Investigation of the scene shows no signs of fire within her room, and the medical examiner observes no external findings on the body. Which of the following conditions best explains the woman's death? A. Acute myocardial infarction B. Cerebral hemorrhage C. Malignant hyperthermia D. Pseudomonas aeruginosa septicemia E. Pulmonary edema

E

A 36-year-old man is the owner of a radiator repair shop, where he works cleaning, cutting, polishing, and welding metals. Over 6 months, he develops worsening malaise with headache and abdominal pains and has difficulty holding his tools. CBC indicates microcytic anemia, and basophilic stippling of RBCs is seen on the peripheral blood smear. An elevated blood level of which of the following would be most useful in determining the toxic exposure causing his illness? A. Alanine aminotransferase B. Calcium C. Creatine kinase D. Selenium E. Zinc protoporphyrin

E

A 36-year-old woman has been using low-dose estrogen-containing oral contraceptives for the past 20 years. She has smoked one pack of cigarettes per day for the past 18 years. She is G2, P2, and both pregnancies ended with term live-born infants of low birth weight, but no anomalies. On physical examination, no abnormal findings are noted. Her BMI is 24. She is at increased risk for developing which of the following conditions? A. Breast carcinoma B. Cholecystitis C. Dementia with Lewy bodies D. Endometrial carcinoma E. Myocardial infarction F. Ovarian carcinoma

E

A 52-year-old woman with a long history of ethanol abuse has had increasing congestive heart failure for the past year. For the past month, she has experienced increasing confusion, disorientation, and difficulty ambulating. Physical examination shows nystagmus, ataxia of gait, and decreased sensation in the lower extremities. Laboratory studies show hemoglobin, 13.1 g/dL; hematocrit, 39.3%; MCV, 90 μm3; platelet count, 269,300/mm3; and WBC count 7120/mm3. A long-term dietary deficiency of which of the following nutrients is most likely to produce these findings? A. Folate B. Niacin C. Pyridoxine D. Riboflavin E. Thiamine

E

A 55-year-old woman has had worsening problems with memory and the ability to carry out tasks of daily living over the past year. She has had watery diarrhea for the past 3 months. Physical examination shows red, scaling skin in sun-exposed areas. Deep tendon reflexes are normal, and sensation is intact. Which of the following diseases is she most likely to have? A. Beriberi B. Cheilosis C. Hypothyroidism D. Marasmus E. Pellagra

E

A 56-year-old man with a 60 pack-year history of smoking has been diagnosed with a squamous cell carcinoma of the larynx. He receives radiation therapy, 40 Sv (4000 cGy) in divided doses, to treat the carcinoma. One year later, endoscopy shows no gross evidence of residual carcinoma. Which of the following adverse effects is most likely to be present in this patient as a result of this radiotherapy? A. Azoospermia B. Cerebral atrophy C. Colonic ulceration D. Marrow aplasia E. Vascular fibrosis

E

7 A 41-year-old woman had a chronic cough for 7 months. She had a positive tuberculin skin test result. A chest radiograph showed multiple cavitary lesions in the upper lobes of the right and left lungs. She was given isoniazid, rifampin, pyrazinamide, and ethambutol therapy. Now on physical examination 6 months later, a peripheral neuropathy is observed. Administration of which of the following nutrients would most likely have prevented the neuropathy? A. Ascorbic acid B. Calciferol C. Calcium D. Cobalamin (vitamin B12) E. Niacin F. Pyridoxine G. Riboflavin

F

A 9-month-old infant has failure to thrive following a premature birth with low birth weight. The infant has chronic cholestatic hepatobiliary disease. The infant is now at the 40th percentile for height and the 25th percentile for weight. On examination, he exhibits absent deep tendon reflexes, decreased vibration and pain sensation, muscle weakness, and abnormalities of eye movement. Laboratory studies show hemoglobin, 9.2 g/dL; hematocrit, 27.6%; MCV, 86 μm3; platelet count, 208,000/mm3; WBC count, 6080/mm3; total protein, 6.4 g/dL; albumin, 3.4 g/dL; glucose, 70 mg/dL; and creatinine, 0.3 mg/dL. A deficiency of which of the following vitamins is most likely to contribute to these findings? A. Vitamin A B. Vitamin B1 C. Vitamin B3 D. Vitamin B12 E. Vitamin C F. Vitamin E G. Vitamin K

F

Sir Robert Falcon Scott reaches the South Pole on January 17, 1912, barely 1 month after Roald Amundsen achieves this goal with a more experienced and prepared expeditionary party. Scott's dejected party must now make the long trip back to their base, but they are weak and running low on supplies, and the weather is unusually cold, even for Antarctica. Finally, they can go no further because of severe storms. Months later, a rescue team finds the bodies of the men. All have a hyperkeratotic, papular rash; ecchymoses; and severe gingival swelling with hemorrhages. Which of the following was most likely a contributing cause of death in these men? A. Beriberi B. Kwashiorkor C. Pellagra D. Pernicious anemia E. Rickets F. Scurvy

F