If a person eats a hamburger that contains infectious particles, called prions, from a sick cow, these particles enter the brain and cause proteins to unfold, causing severe illness.
mad cow disease (bovine spongiform encephalopathy)
A patient presenting with an inability to control their electrolyte balance likely has a problem with which system?
the endocrine system
A woman in her 60s is rushed to the emergency department (ED) after having lost consciousness at a Singing Christmas Tree event. The emergency medical technician (EMT) reports that, in addition to losing consciousness, the woman was tachycardic (with a heart rate of ~100 bpm), warm to the touch and diaphoretic (sweaty). During the physical exam, the patient reported that she had not been feeling well lately, but was not taking medications, had no recent surgeries, and had not been diagnosed with anything. As time passes she slowly becomes a little more coherent, and her heart rate begins to normalize, but she suddenly vomits on the floor. Rapid blood tests reveal hypoglycemia (reduced blood glucose).
A tumor causing over-secretion of insulin.
A young man is brought to the emergency department by his girlfriend complaining of high fever, excessive fatigue, weight loss, dry cough, chest pain, swollen lymph nodes, erythema (red blotchy skin), and small granulomas (raised, reddish, bumps on the skin surface). The girlfriend reports that he had just gotten over a bad cold the previous week. What is the likely problem that the patient is suffering from?
sarcoidosis
A 28-year-old male construction worker is brought to the emergency department (ED) on a particularly warm day. The paramedics were told that he had been working like he normally does, but began to complain about the heat and eventually lost consciousness. Upon arrival in the ED, physical examination reveals very dry skin and a core temperature of 105.4°F. His co-worker explains that he has been sick for the past few days with serious diarrhea, and has been taking prescription drugs to treat this. What is the likely problem the patient is suffering from?
hypohidrosis (inability to sweat)
A 23-year-old woman presents to the dermatologist’s office, complaining of several bumps on her face, ears, and head that began appearing within the last month. Even though it is January, the young woman is deeply tanned. She explains that she has worked at a spa for the past 5 years, and is given free access to the tanning booths. The bumps range from crusty spots to ulcerated bumps. What is the likely problem the patient is suffering from?
skin cancer
A 47-year-old man comes to the emergency room complaining of painful blisters on his arms and inside his mouth. Upon physical examination, the patient presents with large blisters on the insides of his cheeks (buccal surface), his gums, the roof of his mouth, down his throat, and all over the surface of his skin. The blisters are at different stages—some are forming, some are full blisters, and some are already healing. He has a normal body temperature and appears otherwise normal upon physical examination. The patient has blood drawn for analysis and is instructed to discontinue all his medications. Blood analysis reveals no sign of infection or exposure to toxic chemicals, but it does reveal elevated IgG levels against desmoglein I and 3. What might be the cause of the patient’s blisters?
autoimmune destruction of the desmosomes between epithelial cells
A 10-year-old boy was brought to the ED by his mother because of pain in his legs, fatigue, and abdominal pain. His mother stated that his pediatrician told them to come to the hospital right away because her son had appendicitis. After a thorough workup, the physician was able to rule out appendicitis. This began to look like something the physician had only heard about in medical school but had never actually seen in practice. After research and tests, it was concluded that his symptoms were caused by an accumulation of molecular waste products in his cells caused by a genetic mutation in the gene encoding an enzyme responsible for the breakdown of glycolipids. What is the organelle that is tasked with cleaning cells of wastes and debris?
lysosomes
On a cold morning in winter, a family of four is found unresponsive on the floor of their home. The paramedics smell smoke within the house, and the furnace in the basement had malfunctioned during the night. The family is taken to the emergency department (ED) and upon physical examination, all members of the family present with cherry red lips and fingertips, a classical sign of carbon monoxide (CO) poisoning. Carbon monoxide gas is produced during many combustion reactions and interferes with the transport of oxygen through the blood. What cellular organelle is most affected by CO poisoning?
mitochondria
A 32-year-old male was brought to the emergency department after a motor vehicle accident. A drunk driver ran a red light and struck the car in the area where he was seated. The door collapsed in on him and he knew right away that he had broken his femur. The fracture was repaired and the patient was progressing nicely. On the second day, however, he developed dyspnea (difficulty breathing) and shortness of breath. The examining physician noticed small petechiae in the axillary region as well as a few in the oral mucosa. Blood tests revealed a decrease in platelets (thrombocytopenia) and an increase in fat.
fat embolism
An 8-year-old boy comes to the emergency department for a broken arm. He describes his accident as “I felt a pop when I bumped into the wall.” Looking back through his medical history, he has been to this hospital and a few others in his eight short years with various broken bones. The physician immediately begins an abuse protocol to ensure his safety. The physician notices that the reason for the break is usually unknown. An examination of the boy reveals that his right arm has a clear deformity that would indicate a break. The physician also notices that the boy's sclera is bright blue instead of the normal white.
osteogenesis imperfecta
A 24-year-old female brings her 4-month-old son to the clinic because she has been unable to console him over the past week. He is not feeding well, sleeping well, and is not playing like he had been. She is also concerned because his head has begun to “look strange,” as though his forehead is beginning to “get taller.” On examination, the physician observes a well-appearing, but cranky boy, with a head that appears tall and narrow, with a bulge in the anterior aspect of his head.
premature closure of a skull suture
A 64-year-old female presents to a dermatology clinic with concerns about the appearance of her hands. She notes that she has been having pain lately, mostly in the right hand and fingers that is worse when she first wakes up but improves as the day goes on. She says that she had been taking over-the-counter medications for the pain in her fingers. On examination, the review of systems is all within normal limits. On physical examination of her hands, the physician notes a red, swollen middle interphalangeal (MIJ) and distal interphalangeal joints (DIJ). The swollen areas feel bony and hard but are painless to palpation. At the area of the DIJ, the doctor sees small, round, glossy-appearing nodules. She lances one of the nodules and a clear, very slippery fluid comes out.
osteoarthritis
A 6-year-old boy was brought to the ER because his mother was concerned that he had a strange way of walking, he was falling for no reason, and he seemed to tire easily. On physical examination, the young man had very well-developed gastrocnemius muscles in both legs. When asked to walk, his gait was abnormal and he nearly fell twice. When asked to stand up from a lying position, the boy struggled to do so (this is known as Gower’s sign, caused by weak peripheral muscles). There is no evidence that anyone else on his mother’s side of the family suffers from the same problem. The physician ordered a muscle biopsy.
Muscular dystrophy
A 67-year-old female is brought to the ER for difficulty breathing and swallowing. The attending physician notes that she is also suffering from ptosis (one drooping eye). When asked to read back a notice on the wall, the patient tells the physician that everything appears to be doubled, which is resolved with one eye closed. The patient also has altered speech.
myasthenia gravis
A 24-year-old female presents to the ED complaining of intermittent severe pain in her lower legs. She states that this has been occurring since she started preparing for her first marathon last month. She notes that the pain seems to start in the calf area and spreads around to the front of her lower leg over time. She describes the pain as slow onset and leading up to the most excruciating pain she has ever felt, though she can’t exactly pinpoint where the pain is other than her lower leg. She has tried to push through the pain, but it eventually becomes too intense and she has to stop running. The pain does seem to improve after she stops and rests for a while, and it seems to be limited to her left leg. She also remembers that she gets a tingling, pinprick sensation in her foot.
Compartment syndrome is causing the pain.
A young man is brought to the ER after being involved in a motor vehicle accident. The young man did not have his seat belt on and suffered cuts to his forehead and damage to the back of his head. He reports numbness in different parts of his body, difficulty swallowing, poor coordination, and slurred speech. He admits that he had been drinking prior to the accident and that he is a heavy smoker of marijuana.
damage to the medulla
A 7-year-old girl presents to the clinic because her teachers and mother notice that she is falling down more frequently than normal. During the physical examination, the mother says that she is in the special needs classes at school, but had never been diagnosed with anything other than a “learning disability.” The physician immediately notices that she has a strange way of talking and moving that seems almost “robot-like.” The physician asks the patient to stand, tilt her head back, put her arms straight out to her sides, and close her eyes (while the physician is ready to catch her). When she closes her eyes, she immediately falls to her right. When asked to walk her down the hall of the clinic the girl falls three times, but each time, she falls to her right.
damage to the cerebellum
A 63-year-old female presents to the hospital’s dialysis clinic for dialysis. During a routine workup of the patient while receiving dialysis, the charge nurse notices that the woman has no soft tissue associated with her big toe. Palpation of the skin reveals that the skin covers bone and no other tissues. When the nurse asks the patient if she has noticed anything going on with her, the patient replies, “I haven’t felt my feet in years.” The patient is also obese and is being treated for hypertension, hyperlipidemia, and hyperglycemia. Diabetes over time may lead to neuropathy, and abnormal or poor sensations.
diabetic neuropathy had destroyed the nerves over time
A 10-year-old boy is brought to the clinic by his mother because of a strange lump in his right brachial region. His medical history (as related by his mother) includes extreme clumsiness, broken bones, burns, and various cuts and scrapes over the past two years. In the physical exam, the deformity in the right brachial area is easily moved and subsequent x-ray confirms a fracture. The physical examination also reveals scars around his mouth, and the tip of his tongue is missing. Poking the patient’s skin behind his knee with a needle evokes no response.
He has no functional nociceptors.
A 64-year-old male is brought to the emergency room following a motor vehicle accident in which he was driving in the wrong direction. He had sustained serious head trauma and was unconscious and non-responsive to painful stimuli. After several days in the intensive care unit, he had not regained consciousness and did not appear to be improving. During a physical examination, a neurologist stroked the sole of his foot, which caused his big toe to dorsiflex and all of his other toes fanned out.
brain damage
A 42-year-old male was brought to the clinic because he began having difficulties walking and noticed other disturbing signs such as general weakness and he said he felt like he was having difficulty breathing. He was quite concerned because a family member died from a paralytic disease that he could not recall because he was very young at the time. On physical exam, the physician found lower limb muscular atrophy, depressed reflexes, foot drop, and fasciculations (muscle twitching) in his legs. On further examination, he presented with a positive Babinski sign, hyperreactive reflexes in some instances, and spastic muscular contractions.
amyotrophic lateral sclerosis
A 27-year-old woman presents to the emergency department with extreme tachycardia (175 bpm) and hypertension (153/99). An ECG reveals irregularities in her heart rate with intermittent missed beats. The physician also notices upon examination that the patient is perspiring heavily and the pupillary reflex is slowed but not absent. The patient remembers having a bad cold several weeks before the symptoms appeared.
Guillain-Barré syndrome
A 54-year-old man presents to the clinic for a two-week history of anxiety, profuse sweating, heat intolerance, and severe headaches. He notes that these symptoms seem to come and go but that he really notices them when he is working in his garden in the mornings. He also notes that the headache never really goes away. Upon further questioning, he recalls times when he felt like his heart was racing and “beating funny,” like it would “come out of his chest.” During physical examination, his blood pressure is 152/93 (normal 120/80), and it does not decrease after resting quietly for an hour. The attending physician orders a thyroid panel to determine blood levels of T3/T4 and has the patient record his blood pressure for a 24-hour period. The thyroid results are normal.
overproduction of epinephrine