Drug X decreases blood pressure Case Assignment

CASE STUDY ONE

Mary-Lou is a 75-year-old widow, who lost her husband to cancer over a year ago. Her family and friends have noticed that she has been very teary, has low self-esteem, and has lost interest in the things she used to love, such as going to bingo with her friends and gardening. Her family initially put this down to the loss of her husband and thought it would pass with time. However, they are now getting really concerned as they have noticed that Mary-Lou’s mood is not improving still. When asked by her daughter if she is sleeping well, she says she has been drinking wine every night to help her go to sleep because it makes her feel happy and relaxed. What started as one glass a night has now increased to two or three glasses a night, and she has also started drinking during the day. Her daughter has noticed that her mum’s face always appears flushed and that she has had quite a few colds lately. Mary-Lou is also losing her balance and experiencing mood swings. Her daughter is worried that she is relying too heavily on alcohol and fears that she is starting to get short-term memory loss from the alcohol consumption. She has been forgetting things such as where she put her keys, whether she turned on the washing machine, and why she opened the fridge. Further, Mary-Lou tends to forget the topic of conversation when talking with her daughter on the phone and has also been getting disorientated and lost when she goes out on her daily walks. The other day, for example, a neighbour rang her daughter to tell her that she found Mary-Lou wandering around aimlessly, and when questioned what she was doing, Mary-Lou snapped and said she was trying to get home. Her daughter decided it was time to take Mary-Lou to the local GP to work out what was going on with her.

After listening to the signs and symptoms Mary-Lou was experiencing, the GP diagnosed her with depression and prescribed a SSRI to be taken daily. Based on the results of clinical and radiological assessments, the GP determined that she also had early onset Alzheimer’s disease. He prescribed a cholinesterase inhibitor and gave the family information on support groups and tips on what to do from here on in. He also prescribed a tranquiliser to be taken daily.

Question 1 (5 marks)

Based on the description above

• Select/name one of the diseases/conditions Mary-Lou is suffering from and describe two signs and/or symptoms from Mary-Lou’s history that support your selection.
• Explain the pathophysiology of the condition you named Question 2 (3 marks) Explain the mechanism of action of one drug type Mary-Lou is prescribed with and describe how these drug actions help mitigate some of her symptoms. In you answer, make references to the pathophysiology of the relevant disease and relate the chosen drug’s mechanism of action to the aetiology/pathogenesis of the disease.

Question 3 (4 marks)

The following questions relate to a drug called MedZ:

1. MedZ contains 200 mg of the active ingredient in an intestine-solvent capsule. The active ingredient is effectively transported across the intestinal mucosa, which ensures that 78% of the drug is absorbed and enters the portal circulation. The drug undergoes a significant degree of first-pass metabolism, in which process 55% of the drug passing through the liver gets metabolized and therefore degraded to an inactive product. Calculate MedZ’s bioavailability and show your calculations (2 marks). BIOL122 End-of-semester worksheet Semester 2, 2021
2. When administered alone, 82% of MedZ is bound to plasma albumin. However, because of the higher plasma protein binding affinity of another drug, called MedY, when MedZ and MedY are administered together, the bound fraction of MedZ decreases to 35%.
3. Identify the type of drug interaction between MedZ and MedY in the present scenario and give your rationale (1 mark).
4. Assuming that MedZ and MedY are administered together in an elderly patient, explain if the dose of MedZ should be decreased, increased, or left unchanged and give your rationale. (1 marks).

Mary-Lou’s family was happy with the management plan established by the doctor as Mary-Lou was progressing quite well. She was using notepads to jot down reminders, a pillbox to keep her medication organized, and a calendar to record appointments. Her family members were helping her with routine tasks such as cooking and paying bills. She was feeling much happier and did not have to rely on alcohol to go to sleep. One day she was feeling so good she decided to walk to her GP appointment alone. On her way there she stumbled over a branch and fell. She felt excruciating pain in her hip. A passer-by called an ambulance, and she was taken to the emergency department at the Royal Melbourne Hospital. An X-ray revealed that she had hip fracture and had to have surgery to repair it. Mary-Lou wondered whether this was linked to the pain she had been experiencing in her left knee for a while now. The specialist explained to Mary-Lou that the pain in her left knee was likely due to degeneration of her cartilage and said that the fracture might have been due to weakened bones. He told her he would like her to have a bone mineral density test to measure her bone density. The DEXA scan gave a T-score of −3.0. Mary-Lou is now given bisphosphonates and told to increase her daily intake of calcium.

Question 4 (5 marks)

Name the disease affecting Mary-Lou’s left knee and describe two characteristic clinical manifestations of this pathology (2 mark). Explain the aetiology and pathophysiology of the disease (3 mark).

Question 5 (5 marks)

Considering Mary-Lou’s T-score, identify the disease she suffers from, briefly describe the pathogenesis of this disease, describe the mechanism of action of bisphosphonate administration, and explain the benefits of this treatment in her present condition.

Question 6 (3 marks)

Discuss why Mary-Lou’s fracture may take longer to heal than it would for someone who was half her age. In your answer, you are expected to name and discuss three physiological factors that are needed for healing to take place and explain how each of the factors you identified is affected by ageing.

CASE STUDY 2

Hilda Wilde is a 45-year-old woman, who was diagnosed with asthma as a child. She recalls her first asthma attack being horrendous; chest tightness, breathing difficulty, wheezing, feeling anxious, and sweating profusely. She was rushed to hospital and spent many days in hospital as a child until she managed to work out the triggers and control them early. The triggers for her asthma were cold temperature, pollen, smoky environment, and respiratory infection/cold, which continue to be the triggers throughout her adult life. She also developed hay fever and an allergy to penicillin in her 20’s, which didn’t surprise her as her mum also had these conditions.

One cold spring day, Hilda is outside gardening as she is finding herself stressed by the current coronavirus and gardening usually relaxes her. Hilda is making good progress on weeding when she starts to experience those dreaded sensations she knows only too well; tightness in the chest, shortness of breath, and dizziness. She starts to wheeze and cannot stop coughing. Her husband notices Hilda is struggling and brings Hilda’s inhaler (Ventolin) for her. However, Hilda’s wheezing and shortness of breath does not ease off, even with her inhaler. She finds it hard to talk or get up and walk. Her lips start to turn blue. Hilda’s husband calls an ambulance, and Hilda is taken to hospital where she is given corticosteroids. She is told she has to stay in hospital a few days so that her condition can be monitored. However, Hilda is worried about staying in hospital due to the novel coronavirus outbreak. Her GP has previously told her that if she contracts the virus, she is at a greater risk of developing more serious symptoms, such as pneumonia or acute respiratory distress. The hospital staff have assured her that they take all the necessary precautions: all coronavirus-affected patients are isolated in private rooms, and all healthcare staff practice proper hand hygiene and appropriate use of PPE.

A few days later, Hilda’s asthma is under control, and she is now discharged from hospital. She is told to take her preventer medicine every day, even when she is feeling well. She is also told to follow routine practices and precautions to lessen her risk of contracting coronavirus.

Question 1 (2 marks)

Choose one of Hilda’s triggers and explain how it contributes to the pathophysiology of her asthma.

Question 2 (4 marks)

Hilda has been told to take her ‘preventer’ medication everyday.

1. Name the broad drug category preventer medications belong to, describe their mechanism of action, and explain their benefits in Hilda’s case. (2 marks)
2. Describe the method and one benefit of topical administration of preventer medications (2 marks).

Question 3 (2 marks)

Hilda has been advised to get the AstraZeneca vaccine to reduce the risk of contracting coronavirus. She is hesitant as she has heard that the Pfizer vaccine is ‘better’. She doesn’t understand the doctor’s explanation of the two vaccines. Using terms a patient can understand, describe one difference and one similarity between the mechanism of action of the Pfizer and AstraZeneca COVID vaccines.

CASE STUDY 3

Bruce is a 47-year-old journalist, who decides he needs to visit his doctor due to some gastrointestinal symptoms. At first it just started out as a bit of abdominal pain and cramping, followed by diarrhea so at first Bruce just thought he had a stomach bug. But weeks went by and the diarrhea just increased in frequency, and instead of feeling better, he started to feel really fatigued. This had been going on for 8 months before his wife finally convinced him to make an appointment with a doctor, who then referred him to a gastroenterologist. A couple of months later when he finally goes to his specialist appointment, Bruce admits after questioning that he has had bleeding with his stool, but he didn’t want to tell the doctor as he was embarrassed and didn’t want to get checked for hemorrhoids. The gastroenterologist also asks many questions about Bruce’s diet and his weight and discovers that Bruce has lost 15 kg in the past year despite eating a lot of hot chips and mashed potatoes – the only thing Bruce feels doesn’t make his diarrhea worse. The gastroenterologist then tells Bruce he would like to perform a colonoscopy to investigate further. After the colonoscopy, the surgeon tells Bruce that they found a number of polyps in his bowel, which is not necessarily a cause for concern as many polyps are benign, but they will have to wait on the results of the biopsies to make sure none of them were malignant. A week later the surgeon calls Bruce; unfortunately, it is bad news – the biopsy shows evidence that the growth is malignant and anaplastic and that they can’t rule out metastatic growths. Bruce is called back in for follow-up tests, and they find that there is an abnormal growth in his liver also.

Bruce is now sent to an oncologist, who recommends that he has surgery to remove any remaining polyps, a portion of his bowel, and the abnormal growth from his liver. Based on the advice from his oncologist, Bruce also decides to undergo chemotherapy treatment. Whilst doing some routine checks after his treatment, Bruce is informed he has neutropenia.

Question 1 (4 marks)

Describe two similarities and two differences between hyperplasia and cancer.

Question 2 (4 marks)

On follow-up examinations, Bruce is found to have a brain tumour. Biopsy results reveal that the cancer cells taken from his brain tumour have the morphological characteristics of colorectal cancer. Considering brain cells are permanent cells, explain the most likely reason for this finding.

Question 3 (2 marks)

Explain why patients who have leukaemia may have excessively high numbers of white blood cells in their blood, yet they are immunocompromised.

Bruce’s friend Greg has been trying to support him throughout his journey. Greg is a 42-year old ITspecialist, who suffers from type II diabetes mellitus, which has been under control using an oral anti-hyperglycaemic medication and a reasonably healthy diet. Rather disturbingly, however, Greg has been experiencing numbness and some awkward tingling in his left foot recently.

Question 4 (3 marks)

Assuming that Greg’s present symptoms are associated with his underlying disease, name the condition responsible for his numbness and tingling, and explain the link between type II diabetes and the condition you identified.

Question 5 (1 mark)

Greg takes an oral anti-hyperglycaemic medication. Explain why insulin administration is not recommended in his condition.

Question 6 (2 marks)

Explain how glucose uptake of Greg’s (i) endothelial and (ii) resting skeletal muscle cells changes when he is experiencing a hyperglycaemic episode and give your rationale.