### Recent Question/Assignment

Portfolio Case Studies
1. Case Study on Measles – (known also as Morbilli, Rubeola, or English measles)
The recent epidemic of measles, largely in unvaccinated children, caused at least 140,000 deaths globally in 2018.1 In New Zealand (NZ) 2,185 cases had been reported during the 2019 outbreak.2 Measles is highly contagious,3-5 and of those infected 15% require hospitalisation and 1% develop encephalitis, of whom almost a half die or have permanent brain damage.6
Summer, aged two years, has just returned home to NZ after an 18-month round-the-world journey on a yacht. Her parents left the yacht in Vancouver and flew home from there. Because of the travelling, Summer had not been vaccinated, although her mother planned to catch up on the required vaccinations after settling into their home. However, two weeks after returning home, Summer developed a cough, runny nose, inflamed eyes, sore throat, fever and a red, blotchy skin rash. After attending the family’s general practice,
Summer was diagnosed with measles. xx
1. Describe the immune response to the measles infection that will enable Summer to fully recover and develop immunity against the measles virus .
2. The initial vaccine for measles, mumps, and rubella (MMR) is typically given to infants aged 12-15
months.5 6 Explain the main reasons why this is not given within the first few months of life.
3. The reproduction number or R-nought (R0) for measles is 12-18.7
a) Explain what this means in relation to measles?
b) R0 is also used to work out what proportion of the population need to be vaccinated to prevent the spread of measles. This is calculated by 1-(1/R0).8 Calculate the proportion of people who need to be vaccinated and explain what this mean in terms of 'herd immunity' for measles.
2. Case Study on Glandular Fever
Harry is a 19-year-old, second year University student and is living away from his home city. Harry is a high performing student, is very social, and is a top water polo player (having recently represented New Zealand (NZ) in a European competition). After returning to his University studies he felt feverish, developed a sore throat (pharyngitis) and headache, and generally felt unwell. After being taken to the University’s Health Centre by one of his flatmates for a full physical examination and blood test, he was diagnosed with infectious mononucleosis (glandular fever). Harry’s white blood cell count was 15.5 x109/L, and he tested positive for the 'mono spot test' indicating that he had developed heterophile antibodies, which are associated with the
Epstein-Barr virus.9-11
The consulting general practitioner and practice nurse explained that recovery is usually 3 to 4 weeks but sometimes a relapse is experienced. They advised him to rest (including no water polo), to maintain fluids and take regular Panadol and throat gargles to manage the pain and high temperatures. They also explained what precautions he should take to protect others from this infection.
1. Describe how the Epstein-Barr virus is able to avoid immune destruction and cause persistent infection.
2. Avoidance of contact sport is important during the recovery period because of the rare possibility of splenic rupture. Explain how infectious mononucleosis could cause splenic rupture?
3. Although pharyngitis is a common symptom in infectious mononucleosis, it is important to always take a throat swab in addition to the 'mono spot test'. Explain the reason for the throat swab?
3. Case Study on Whooping Cough
Sally is almost four years old and attends a local preschool. Over the past few days Sally’s mother, who is 34 weeks pregnant, noticed that Sally was sneezing, with a runny nose and a slight cough, and assumed Sally had a typical 'cold'. However, four days after developing this 'cold' Sally started having coughing fits and vomiting. After taking Sally to the family’s general practitioner, she was diagnosed with whooping cough caused by Bordetella pertussis.
Whooping Cough is very contagious, and in certain circumstances is a notifiable disease.12 Despite widespread vaccination, there continues to be frequent outbreaks of whooping cough in most countries.13-16 Sally was prescribed erythromycin. Other close members of the family were advised to see their general practitioner (GP) for antibiotic prophylaxis. Sally’s mother was also given the pertussis vaccine. Readings
(Reading Defence 6) and (Reading Defence 7) will assist you with completing this case study.
1. During the consultation, Sally’s mother described how frightened she feels when Sally 'whoops' and turns blue during a coughing fit. Describe the typical cough. Explain what causes the 'whoop' sound and why Sally turns blue during a coughing fit.
2. Sally mother is concerned that her newborn baby might become infected with Bordetella pertussis and develop whooping cough. The GP explains that this is most unlikely because Sally’s mother has just received the pertussis vaccine. Explain the rationale for this. In your answer include explanations of the immune responses in:
a. Sally’s mother after receiving the vaccine and
b. If her new baby if exposed to Bordetella pertussis following birth?
4a. Cardiovascular Disease - Adult Case Study (Complete either 4a OR 4b)
Answer either the questions relating to Mrs Parks (adult) OR Luka (paediatric) case study.
Mrs Parks is 62 years old and has been admitted to hospital with a tentative diagnosis of a non-ST segment elevation myocardial infarction (NSTEMI). Further tests, including a 12-lead electrocardiogram (EGG) and echocardiogram, confirmed the diagnosis, revealed a partial blockage in her left anterior descending artery, ischemia in the bundle of His and sub-endocardium of the left ventricle and a left ventricular ejection fraction of 70%. Cardiac surgery has been scheduled to insert a stent and re-establish patency in the affected vessel.
Mrs Parks undergoes regular mammography and cervical screening. She seldom needs to see her general practitioner and has never been prescribed any long term medications. She started smoking after leaving school, and although she has not managed to quit after several attempts, she has reduced the number of cigarettes smoked to about 8 per day. Mrs Parks had a deep vein thrombosis following elective gynaecological surgery 7 years ago that was treated with heparin initially, followed by warfarin for 3 months.
Mrs Parks works as a mid-level manager in a popular inner city restaurant and tends to drink 1-3 glasses of wine each day. She has a BMI of 23. She describes herself as usually fit and healthy and explained that she is 'on her feet all day while at work' and walks the family dog on her days off. She is supported by her partner of 10 years and has an adult daughter, who lives in the same city, and son who lives overseas.
Currently her condition is stable. Her blood pressure is 150/90 mmHg, heart rate is 90 beats per minute and respiratory rate is 18 per minute. Her blood results following admission are outlined below.
Biological variable Patient results Normal range
Haemoglobin 135 g/L 115–145 g/L
HbA1c 31 mmol/mol 41 mmol/mol
Haematocrit 0.40 % 0.35–0.45 %
White blood cell count 4.0 x 109/L 4–1 x 109/L
Total cholesterol 5.6 mmol/L 5.0 mmol/L
Low-density lipoprotein cholesterol (LDL-C) 3.9 mmol/L* 3.4 mmol/L
High-density lipoprotein cholesterol (HDL-C) 1.2 mmol/L 1.0 mmol/L
Triglycerides (TAGs) 0.8 mmol/L 1.7 mmol/L
Total cholesterol: HDL ratio 4.7 mmol/L 4.5 mmol/L
Microalbuminuria 5 mg/L 30 mg/L
Troponin T 70ng/L 15ng/l
C-reactive protein (CRP) 8mg/L 1mg/L
Sodium 142 mmol/L 135–145 mmol/L
Potassium 5.3 mmol/L 3.5–5.3 mmol/L
Oxygen saturation 93% 95 – 100%
PaO2 80 mmHg (10.7 kPa) 80–100 mmHg (10.7–13.3 kPa)
PaCO2 31 mmHg (4.1 kPa) (35–45 mmHg) (4.7–6.0 kPa)
pH 7.37 7.35–7.45
Actual bicarbonate 24 mmol/L 23 – 28 mmol/L
*Estimated
1. State the three major risk factors Mrs Park exhibits that are associated with cardiovascular (CV) disease and explain how each one contributes to the development of atherosclerosis.
2. Explain the significance of elevated Troponin T in relation to the diagnosis of a NSTEMI.
3. Post–menopausal women have a similar risk of major CV events as men, and a higher prevalence of hypertension and stroke.17 CV disease is also the leading cause of death in older women.18 Despite this, women are often prescribed less cardioprotective medications than men are.17 19-21 State and discuss the numbers of women (with a similar risk profile as Mrs Parks) who 'need to be treated' with antihypertensive medication to prevent one woman having a major CV event. The following resources (Reading Cardiovascular 12) and (Reading Cardiovascular 13) and the on-line tutorial on NNT will assist you in answering this question.
4b. Cardiovascular Disease - Paediatric Case Study
Luka is 12 years old. Four years ago, he developed bacterial (infective) endocarditis following a skin infection and cellulitis on his leg. The infection was caused by staphylococcus aureus. He was treated with antibiotics and appeared to fully recover. However, while playing soccer at school he noticed that he became more breathless when running than the other boys on the team. During a recent game of soccer, his coach, who recognised that Luka was struggling to run for the ball, directed him off the field and to sit down until he recovered.
After Luka had recovered, his mother took him to the local Emergency Department so that he could be fully assessed and treated appropriately given his history of endocarditis. Following extensive tests, Luka was diagnosed with aortic stenosis secondary to endocarditis22 23 and an echocardiogram showed extensive aortic valvular vegetation.
1. It is important to reduce Luka’s risk of further infections.24 Good dental hygiene reduces the risk of oral and systemic infections. Explain the reason for this and describe what measures his parents could take to ensure good dental hygiene.
2. Aortic stenosis affects blood flow from the left ventricle into the aorta.25 Explain the resulting compensatory changes that take place in the left ventricle to maintain stroke volume (ejection fraction), including additional changes in children.
3. After a three-month recovery period Luka returns to school. About a month later Luka stumbles and falls while running with his friends. When Luka’s teacher finds him, he is unable to sit up and appears confused and not able to communicate clearly. His teacher realises this is a medical emergency, calls an ambulance to take Luka to hospital and lets his parents know what happened. Explain the likely cause for this incident and how it may be treated?
4. Luka is prescribed a six-week course of the antibiotic cefazolin. Adverse drug reactions (ADR) are common with this anti-staphylococcal medication. One meta-analysis compared cefazolin to anti-staphylococcal penicillins.26 Using data from this study, the numbers needed-to-treat (NNT) to prevent therapy interruption from ADRs for cefazolin compared to penicillin was 11.
Explain what this means in relation to benefits and risks for Luka. The following resources (Reading Cardiovascular 12) and (Reading Cardiovascular 13) and the on-line tutorial on NNT will assist you in answering this question.
5. Acid Base Case Study
A new zoonotic virus COVID-19 transmitted from bats to people in 2019 led to the global pandemic.27 28 Most people infected suffered mild to moderate signs and symptoms and recovered at home. However, 5-10% of people infected required hospitalisation, and of those, a small proportion also required respiratory support
in intensive care.29 30
Mr James, aged 76 and residing in an aged-care facility, was admitted to the intensive care unit (ICU) about a week after developing symptoms of COVID-19 and having difficulty breathing. On admission to the ICU he had a nasal swab taken for viral testing (including COVID-19 and influenza subtypes) and an arterial blood sample before receiving oxygen support.
Based on Mr James’ signs, symptoms and blood test results he is exhibiting an acute exacerbation of respiratory failure most likely due to a COVID-19 infection. His breathing is rapid and shallow (respiratory rate is 30 per minutes), heart rate is 110 beats per minutes and his blood pressure has increased since admission from 140/90 to 150/93. He is currently receiving oxygen via a high flow nasal cannula circuit to support his breathing and improve is oxygenation levels.
Mr James' arterial blood gas and electrolyte results.
Indices Results Normal
pH 7.05 7.36–7.44
O2 saturation (room air) 89 % 90%
PaO2 72
9.6 kPa mmHg 80–100 mmHg
10.7–13.3 kPa
PaCO2 58
7.7 kPa mmHg (35–45 mmHg)
(4.7 – 6.0 kPa)
Bicarbonate (HCO-3) 21 mmol/L 21 – 27 mmol/L
Base Excess -4 -2 - +2
Lactate (Lactic acid) 1.6 mmol/L 1 mmol/L
C-reactive protein (CRP) 30 mg/L 5 mg/L
Blood glucose level (Non-fasting) 9.6 mmol/L 3–11 mmol/L
Potassium 5.1 mmol/L 3.5–5.2mmol/L
Sodium 140 mmol/L 135–145 mmol/L
1. State the type of acid base imbalance.
2. Explain the origin of the acid base imbalance and include the bicarbonate equation with the direction of the chemical flow in your answer.
3. Is there any compensation occurring? If so, describe the type of compensation?
4. Explain the effect of this pH imbalance on the transportation of oxygen.
6a. Renal Disease - Adult Case Study (Complete either 6a OR 6b)
Answer either the questions relating to Mr Johnson (adult) OR Jacqui (paediatric) case study.
After working through the on-line course content the following readings (Reading Renal 3) and (Reading Renal 4) will help you complete the case study about Mr Johnson who has an acute kidney injury (AKI).
Mr Johnson lives independently and alone after his wife passed away 2 years ago. Mr Johnson had just celebrated his 90th birthday with two elderly friends and family. He completed the celebration with a 10-year old prized bottle of Scottish whiskey. The morning following his celebration, he called his daughter to say he was feeling terrible, had a dreadful headache, his mouth felt as 'dry as a bone', and he was unable to pass urine. When Mr Johnson’s daughter arrived at his house, she noticed he was also quite confused and decided to take him to hospital (as it was Sunday and his general practice was closed). After being assessed and having a full blood screen he was diagnosed with AKI and admitted to hospital.
Mr Johnson is reasonably healthy and plays the occasional game of golf with his friends. Although he does not have any chronic medical conditions, he has been prescribed atorvastatin and a beta blocker to reduce his slightly elevated low-density lipoprotein cholesterol and blood pressure and lower his risk of having a cardiovascular event. Mr Johnson had taken Ibuprofen 2-3 times in the night and again in the morning for his headache, when he also had his usual atorvastatin and beta blocker.
Currently his blood pressure is 100/65mmHg, respiratory rate 20 per minute, heart rate 85 beats per minute and temperature 37°C. Based on Mr Johnson’s presentation and blood test results (outlined below), he was diagnosed with Acute Kidney Injury (AKI).
His blood and urine test results are outlined below:
Biological variable Patient results Normal range
White blood cell count 4.5 x 109/L 4 –11 x 109/L
Haemoglobin 135 g/L 115–145 g/L
Haematocrit 47 x 109/L 35–45 x 109/L
Mean cell volume 84 fL 75 – 90 fL
Sodium 152 mmol/L 135–145 mmol/L
Potassium 5.3 mmol/L 3.5–5.3 mmol/L
Total cholesterol 4.8 mmol/L 5.0 mmol/L
HDL cholesterol (HDL-C) 1.1 mmol/L 1.0 mmol/L
LDL cholesterol (LDL-C) 3.6 mmol/L (estimated) 3.4 mmol/L
Triglycerides (TAGs) 0.7 mmol/L 2 mmol/L
Total cholesterol: HDL ratio 4.4 mmol/L 4.5 mmol/L
Microalbuminuria 48 mg/L g/L
Serum creatinine 110 µmol/L µmol/L
Urinary albumin: creatinine ratio (ACR) 60.2 mg/mmol 30 mg/mmol
Estimated glomerular filtration rate (eGFR) 45 ml/min/1.73m2 eGFR 60 ml/min/1.73m2 31

1. Explain the underlying reasons why Mr Johnson’s eGFR is lower than normal.
2. Following hospital admission Mr Johnson’s beta blocker was immediately withheld. Explain the rationale for this.
3. Acute management is aimed at reversing AKI and restoring homeostasis.32 Intravenous fluids are commenced with frequent measurement and readjustment of fluid intake based on urine output and vital observations. Discuss the expected improvements in Mr. Johnson’s symptoms, vital signs, test results and avoidance of complications associated with administering intravenous fluids.
6b. Renal Disease - Paediatric Case Study
Jacqui, aged 5 years, presented to her general practitioner with moderate generalised pain in her abdominal region, a high temperature (41°C) and chills, frequent and painful urination, proteinuria and haematuria. Her general practitioner advised Jacqui’s parents to take Jacqui to Emergency Department at their local hospital because she might need intravenous antibiotics, and then phoned to advise the senior medical officer in advance of their arrival. On presentation at the Emergency Department, Jacqui’s pain had worsened, her blood pressure was 120/80 mmHg and pulse 120 beats per minute.
Reducing her pain was the initial priority and Jacqui was prescribed intravenous morphine and oral paracetamol. Further questioning of her parents revealed that Jacqui had previously had a urinary tract infection, had been 'difficult to toilet train', still wets her bed reasonably frequently and occasionally has some daytime urine leakage particularly if she cannot go to the toilet regularly.
After her pain subsided further tests were arranged. An investigative ultrasound examination revealed minor renal swelling and ureteral dilatation. Jacqui was admitted to hospital and commenced on intravenous gentamicin. Jacqui was encouraged to drink plenty of water and her fluid intake and urine output were monitored.
Jacqui’s blood and urine test results are outlined below (with age-specific reference range):
Biological variable Patient results Normal range
White blood cell count 15 x 109/L 4.5 – 12 x 109/L
Haemoglobin 120 g/L 113 –145 g/L
Haematocrit
0.45 % 0.33 – 0.42 %
Mean cell volume 75 fL 74 – 87 fL
Sodium 145 mmol/L 135 –145 mmol/L
Potassium 5.2 mmol/L 3.5 – 5.3 mmol/L
Serum creatinine 118 µmol/L 25 – 70 µmol/L
Microalbuminuria 45 mg/L 30 mg/L
Urinary albumin: creatinine ratio (ACR) 40 mg/mmol 30 mg/mmol
Estimated glomerular filtration rate (eGFR) 80 ml/min/1.73m2 eGFR 90 ml/min/1.73m2
Microscopy urinary analysis revealed haematuria. A midstream urine culture indicated high levels of Escherichia coli (E. Coli), which is the most common cause of urinary tract infection,33 and sensitivity to gentamicin.
Following test and examination results, Jacqui was diagnosed with an acute pyelonephritis and urinary tract infection, secondary to a urinary tract anomaly. This is most commonly due to an ectopic ureter or abnormal insertion of the ureter into the bladder, which is associated with vesicoureteral reflux.34
Jacqui was discharged after three days, with a normal glomerular filtration rate, greatly reduced proteinuria and haematuria and mild residual pain, indicating effective antibiotic treatment.35 36 Augmentin (oral amoxicillin and clavulanate)37 was prescribed for ten days, and paracetamol as required. Jacqui was referred to the urology team for follow-up x-ray imaging to check for retrograde urine flow or a structural abnormality that could explain her history of urinary problems and recent pyelonephritis.
1. Describe the virulent factors of E. Coli that have resulted in Jacqui developing pyelonephritis.
2. Explain how pyelonephritis leads to albuminuria and haematuria.
3. Discuss the reasons why Jacqui was treated with intravenous gentamicin and encouraged to drink water.
7. Type 1 Diabetes Case Study
Moana is a slim 19-year-old Maori woman who presented to the emergency department with an upper respiratory tract infection, fatigue and nausea. On further questioning, she complained of having a sore throat earlier in the month and a two-week history of polyuria and polydipsia. She also mentioned that her usually tight-fitting jeans were quite loose.
On presentation her heart rate was 100 beats per minute, blood pressure was 105/65 mmHg, respirations 25 breaths per minute and temperature 37.5oC. Based on her presentation and blood test results outlined below, a tentative diagnosis of type 1 diabetes was made, and will be confirmed if she tests positive for islet cell antibodies.
Her grandfather had type 2 diabetes, but no other close relatives have diabetes. Moana often has a cigarette when she is out socially. She is not currently on any medication and works and studies part-time in the hospitality industry. She lives with her parents and three siblings, is usually quite active and plays competitive netball.
Moana’s blood test results on presentation.
Biological variable Patient results Normal range
Capillary glucose 27 mmol/L 7.0 mmol/L
HbA1c 66 mmol/mol 41 mmol/mol
PaCO2 23.0 mmHg 35 – 45 mmHg
Oxygen saturation 99% 95 – 100%
pH 7.32 7.35 – 7.45
Actual bicarbonate 24 mmol/L 23 – 28 mmol/L
Potassium (K+) 5.5 mmol/L 3.5 – 5.3 mmol/L
Sodium (Na+) 145 mg/mmol 135 –140 mg/mmol
Serum creatinine 92 umol/L 45 – 90 umol/L
Urea 5.7 mmol/L 3.6 – 5.0 mmol/L
Serum ketones 5.4 mmol/L 0.1 mmol/L
Haemoglobin (Hb) 140 g/L 115 – 155 g/L
White blood cell count 9 x 109/L 4 – 11 x 109/L
Mean cell volume (MCV) 105 fL 80 – 99 fL
1. Proteins on bacteria and viruses are called antigens.38 Explain why major histocompatibility complexes (MHC) on beta cells are referred to as antigens in people diagnosed with type 1 diabetes. (Include discussion of the immune system in your answer.)
2. Moana has classic signs and symptoms of diabetic ketoacidosis (DKA). Explain the hormonal and metabolic changes that result in ketoacidosis.
3. Following diagnosis and recovery from DKA, it is most important for Moana to achieve normoglycemia (through exogenous insulin, appropriate nutrition and physical activity), and not smoke to prevent microvascular complications (retinopathy and nephropathy).39 Discuss the rationale for focusing management on glycaemic control rather than cardiovascular risk factors.
8. Type 2 Diabetes and Related Complications Case Study
Mrs Talakai is aged 50 years of Pacific ethnicity, has five children aged between 12 and 25 years, and developed gestational diabetes mellitus (GDM) during her last pregnancy. Her serum glucose levels returned to within the normal range following her last pregnancy. However, five years ago her HbA1c increased to 65mmol/mol and she was diagnosed with type 2 diabetes.
Mrs Talakai works four days a week as a teacher aid and is active in her local community. Mrs Talakai and her husband, who is self-employed, support Mrs Talakai’s elderly mother and sister who both have type 2 diabetes. Mrs Talakai is aware that women who develop GDM have a 60% lifetime risk of developing type 2 diabetes,40 and are at higher risk of having a heart attack regardless of whether they remain normoglycemic or develop type 2 diabetes following delivery.41 She is also concerned that her children, who are all overweight but active in sports, are also at risk of developing type 2 diabetes. For these reasons, she is very motivated to improve the family’s lifestyle and reduce these adverse health outcomes.
Currently Mrs Talakai’s BMI is 34, blood pressure 150/87mmHg and she is physically active while at work. Mrs Talakai started smoking after leaving school but stopped during her first pregnancy. Her prescribed medications include metformin (1000mg/day), gliclazide (40mg/day), atorvastatin (20mg /day), aspirin and cilazapril. Her microalbuminuria level has increased over the last three years.
Mrs Talakai’s recent blood and urine test results are outlined below.
Biological variable Patient results Normal range
Fasting Glucose 9.2 mM 4 – 7 mM
HbA1c 63 mmol/mol 41 mmol/mol
Haematocrit 0.40 % 0.33–0.42 %
Total cholesterol 5.4 mmol/L 4.0 mmol/L
Low-density lipoprotein cholesterol (LDL-C) 3.9 mmol/L* 2.0 mmol/L
High-density lipoprotein cholesterol (HDL-C) 1.1 mmol/L 1.0 mmol/L
Triglycerides (TAGs) 2.9 mmol/L 1.7 mmol/L
Total cholesterol: HDL ratio 4.9 mmol/L 4.0 mmol/L
Microalbuminuria 55 mg/L g/L
Serum creatinine 80 µmol/L µmol/L
Urinary albumin creatinine ratio (ACR) 3.9mg/mmol ACR 2.5 mg/mmol (men) ACR 3.5 mg/mmol (women)
Glomerular filtration rate (eGFR) 80 ml/min/1.73m2* eGFR 90 ml/min/1.73m2
* Estimated
1. Referring to Mrs Talakai’s profile above, identify risk factors associated with the development of type 2 Diabetes.
2. Insulin resistance increases in all women during the second and third trimester.42 Explain how and why maternal insulin resistance increases during pregnancy.
4. Based on the latest New Zealand cardiovascular risk guidelines,43 44 Mrs Talakai has an elevated risk of having a major cardiovascular event (heart attack, stroke or a peripheral vascular event) over the next five years. Discuss the best evidence-based management principles for reducing Mrs Talakai risk of having a major cardiovascular event in the future.
9. Asthma Case Study
Maria is aged 24 years and immigrated to New Zealand from Serbia when she was 14 years old. She reported having mild asthma symptoms when she was young, but never required medical attention for these symptoms. Since arriving in New Zealand, she has experienced several episodes of mild asthma-like symptoms (shortness of breath, episodes of coughing during the night and an expiratory wheeze), which progressively worsened over time.
After one acute episode at 17 years, Maria was diagnosed with asthma by her general practitioner and prescribed Flixotide (fluticasone; 2 puffs twice per day), and Ventolin (salbutamol) as required. She regularly woke at night with difficulty breathing in her mid-to-late teens and had to give up playing netball because her asthma and fatigue made it hard for her to train. Maria completed a degree in arts and design and now works as a graphic designer. She is 170 cm tall and weighs 74 kg.
Maria has been brought to the local Emergency Department by her friends, during a severe asthma attack which started while attending a friend’s flat-warming party in a house with cats. Although Maria used her friend’s Ventolin inhaler, her symptoms did not appear to improve, and a recent winter cold appeared to exacerbate the symptoms. Upon arrival at the Emergency Department she was very distressed, unable to speak using full sentences, was short of breath with a sensation of chest tightness and exhibited both expiratory and inspiratory wheezing. Her oxygen saturation (SpO2) was 88%, heart rate 130 per minute, respirations 32 per minute and she was using her accessory respiratory muscles to breathe. Her peak expiratory flow (PEF) was 200 L per minute (45% of predicted value; 449 L per minute) and auscultation revealed a loud expiratory wheeze. She admitted to the consulting doctor that she often forgets to take her Flixotide medication.
Maria was given Ventolin via a spacer, six puffs every 20 minutes and 40 mg of oral prednisone as recommended.45 As this did not provide immediate relief, she was also given six puffs of ipratropium bromide. After 60 minutes her peak flow improved to 310 L per minute, respirations 25 per minute, heart rate 90 beats per minute, SpO2 94% and her use of accessory muscles and expiratory wheeze were reduced.
Maria’s current symptoms continued to improve, and her peak flow was 360 L per minute after 2 hours. Maria was discharged in the early hours of the morning into the care of her parents. She was prescribed 40 mg oral prednisone for 5 days, in addition to Seretide (fluticasone propionate 50 mcg/salmeterol 25 mcg) 2 puffs per day and Ventolin as required. Maria was reminded to ensure she has up-to-date inhalers and to be vigilant in taking Seretide in the morning and evening to reduce the risk of further acute episodes of asthma.
1. Tumour necrosis factor (TNF)-alpha is thought to have a wide range of pro-inflammatory effects in the pathophysiology of asthma.46 Explain how TNF-alpha acts to exacerbate Maria’s asthma allergic response.
2. Some individuals with asthma develop irreversible structural changes to airways known as remodelling.47 48 Describe these chronic changes and explain how they are likely to affect Maria’s symptoms.
3. Breathing exercises, such as Papworth, Buteyko, and yoga methods, are commonly used as nonpharmacological strategies for managing symptoms and the impact of asthma on daily life.49 50 51 Explain the main aims of such breathing exercises and how these are thought to reduce breathing-related symptoms.
10a. COPD Adult Case Study (Complete 10a OR 10b)
Answer the questions relating to Mrs Brooks (adult) OR Marta (paediatric) case study.
Mrs Brooks, aged 70 years of Maori ethnicity, is a retired office manager from Wellington, who lives alone after her husband passed away last year. She was diagnosed with chronic bronchitis, a chronic obstructive pulmonary disease (COPD), 10 years ago and has experienced several exacerbations since, including a prolonged one during the previous winter. She has smoked for most of her adult life, and although she has not been able to stop for any length of time, she has greatly reduced her cigarette use to about five per day.
Mrs Brooks is currently consulting with her general practitioner (GP) while experiencing another exacerbation following an upper respiratory viral infection. She complains of gasping for breath during light exertion such as when quickly standing and walking to answer the telephone. She has regular bouts of productive coughing, including prolonged episodes over the previous three winters, and on some days had found it difficult to dress and stay up for the day. On examination, Mrs Brooks had a pronounced wheeze and fits of coughing with clear sputum. She also has moderate to severe peripheral oedema in her lower legs, ankles and feet, and a slight cyanosis, particularly in her face and nose.
Mrs Brooke’s BMI is 34 kg/m2, blood pressure 140/85mmHg, temperature 36.1 and FEV1/FVC was 66%. Mrs Brooks regular medications include captopril, atorvastatin, aspirin and a Serevent inhaler. After the examination and due to her low eosinophil count, she was prescribed Seretide instead of Serevent,52 and referred her to a new community smoking cessation programme. Her GP will telephone her over the next few days to check of her progress and arrange further follow up if required.
Mrs Brook’s blood and respiratory recent test results.
Biological variable Patient results Normal values (mean±SD)
HbA1c 38 mmol/mol, 42 mmol/mol
Haemoglobin 160 g/L 115 – 155 g/L
Haematocrit 0.48 L/L 0.34 – 0.46 L/L
Mean cell volume 85 fL 80 – 99 fL
C-reactive protein 29 mg/L 0 – 5mg/L
White blood cell count 16 x 109/L 4.0 – 11.0 x 109/L
Neutrophils 4.5 x 109/L 1.9 – 7.5 x 109/L
Eosinophils 0.08 x 109/L 0.0 – 0.5 x 109/L
Forced Vital Capacity (FVC) 2.80 L (2.5 ± 0.4 L)
Peak Expiratory Flow (PEF) 5.50 L/s (5.8 ± 0.9 L/s)
Forced Expired Volume in 1 s (FEV1) 1.85 L (2.1 ± 0.3 L)
Total cholesterol 5.2 mmol/L 5.0 mmol/L
Low-density lipoprotein cholesterol (LDL-C) 3.5 mmol/L 3.4mmol/L
High-density lipoprotein cholesterol (HDL-C) 1.2 mmol/L 1.0 mmol/L
Triglycerides (TAGs) 1.3 mmol/L 1.7 mmol/L
Total cholesterol:HDL ratio 4.3 mmol/L 4.5 mmol/L
Serum creatinine 50 µmol/L 25 – 70 µmol/L
1. Explain how nicotine and other toxins from cigarette smoke contribute to the pathological changes associated with chronic bronchitis.
2. Mrs Brooks presents with moderate to severe peripheral oedema, which is associated with chronic bronchitis.52 Explain how chronic bronchitis can cause lower limb oedema.
3. Referring to GOLD guidelines,52 explain the likely reason why her GP has changed her medication from Serevent (salmeterol xinafoate) to Seretide (salmeterol xinafoate/fluticasone propionate).
10b. Bronchiolitis Paediatric Case Study
Marta aged ten months, of Maori ethnicity, was born at 36 weeks gestation, and was discharged home at 38 weeks, after recovering from some initial respiratory distress and neonatal jaundice. Despite being breastfed for about six months, she has had two respiratory viral infections but is meeting all her milestones. Marta’s parents, who are both teachers, have only recently moved to Auckland for her father to commence a new teaching role. The family are currently living in rental accommodation. Marta has two older brothers who each attend preschool and primary school.
Two days ago, Marta’s parents noticed she was very tired, her breathing was faster than usual, with brief spells of apnoea, and she had lost her interest in drinking and taking solids. Because of Marta’s premature birth and previous respiratory infections Marta’s parents took her to their local hospital’s Emergency Department for assessment and care. Following a full examination, Marta was tentatively diagnosed with bronchiolitis, probably caused by the respiratory syncytial virus (RSV)53, and was admitted to hospital with her mother.
1. Explain what intercostal retraction and nasal flaring indicate in an infant with bronchiolitis.
2. Corticosteroids are not routinely used in the treatment of infant bronchiolitis. Explain the reasons for this.
3. Marta’s mother asks what can be done to prevent Marta getting another bout of bronchiolitis.
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