Multiple Myeloma, Cushing Syndrome, Familial Hypercholesterolemia, Covid-19 Case Studies

Multiple Myeloma

A 65-year-old man was admitted to the hospital with back pain, nausea, vomiting, and loss of appetite. On bone marrow aspiration and biopsy– a marked increase in plasma cells was observed. Serum protein electrophoresis showed a prominent M band in a gamma globulin region.

Question 1. Mention your probable diagnosis.
Answer:

• Multiple myeloma.
• A plasma cell tumor is characterized by multiple punched-out lesions in the bone (spine and chest). An osteolytic lesion in the bone leads to pain and fractures.

Read And Learn More: Biochemistry Clinical Case Studies With Answers

Question 2. What could be the reason for M-band in electrophoresis?
Answer:

• These are abnormal immunoglobulin fragments produced by the proliferation of plasma cells.
• These monoclonal antibodies get accumulate at a single band in a gamma globulin region in electrophoresis known as M-band.

Question 3. Mention the laboratory tests for diagnosis of the disease.
Answer:

• Serum electrophoresis.
• Classical M-band on electrophoresis.

• Heat test on a urine sample.

Bence-jones proteins are light-chain proteins excreted in patients with MM. This protein shows characteristic properties in heat tests. They coagulate at temperatures between 50–60˚C. The coagulum disappears on increasing temperature and again reappears on cooling.

 

Cushing Syndrome

Also Known as Hypercortisolism.

It is due to the hypersecretion of cortisol by any cause.

• When it is due to adrenal pathology it is a primary disorder.
• When it is due to ACTH secreting pituitary adenoma it is known as secondary or Cushing disease.
• When it is due to hypersecretion of CRH from the hypothalamus it is known as tertiary hypercortisolism.

Cushing Syndrome Clinical Symptoms

1. Increased BP.
2. Rapid weight gain and abdominal obesity.
3. Thinning of arms and legs.
4. Fat lump behind the neck (buffalo hump).
5. Round face (moon face).
6. Weak muscles and bone.
7. Excessive sweating.
8. Thinning of skin, stretch marks, easy bruising.
9. Insomnia, infertility, amenorrhoea.
10. Hyper-pigmentation of skin.

Cushing Syndrome Causes

1. Excessive cortisol therapy.
2. Pituitary adenoma (Cushing disease).
3. Adrenal tumor or hyperplasia.
4. Tumors in other parts of the body.

Cushing Syndrome Diagnosis

1. Dexamethasone suppression test.
2. Measuring the cortisol level in response to injection of dexamethasone.

Cushing Syndrome Treatment

1. Stop the cortisol therapy by tapering the dose.
2. Surgical removal in case of pituitary or adrenal adenoma.
3. Treatment of the cause.

Case 1

A 35 years old woman came to OPD with 16 Kg weight gain in 1 year. She also complained of fatigue, depression, sleep disturbance, and easy bruising. She has a history of polycystic ovarian syndrome 7 years back. She has a history of clomiphene-induced pregnancies. Laboratory investigation showed elevated serum cortisol levels with the loss of diurnal variations.

Question 1. What is your probable diagnosis?
Answer: Cushing syndrome.

Case 2

A 62 year old woman came to OPD with weight gain. She developed hypertension and DM over the last 3 years. She also developed muscle weakness in the lower limb 6 months ago. Physical examination showed BP– 160/96 mmHg, facial hirsutism, central obesity, abdominal striae, and peripheral edema. Laboratory investigation showed elevated serum cortisol levels with the loss of diurnal variations.

Question 1. What is your probable diagnosis?
Answer: Cushing syndrome.

 

Familial Hypercholesterolemia

Case 1

A 32 years old woman was hospitalized with acute myocardial infarction. Her plasma cholesterol was found to be 420 mg%, but her plasma triglyceride was normal. Her LDL level was highly elevated. Coronary angiography revealed the presence of severe atherosclerosis in all three coronary arteries. Her father and brother were also found to have hypercholesterolemia.

Question 1. What is the diagnosis?
Answer: Familial hypercholesterolemia.

Question 2. LDL is responsible for the transport of cholesterol from the liver to peripheral tissues.
Answer: LDL level causes atherosclerosis. LDL concentration is directly proportional to plaque formation in arteries. Oxidized LDL gets stacked on the damaged arteries and leads to clot formation and rupture.

Question 3. What treatment is given to reduce cholesterol levels?
Answer:

• Statins– Lovastatin, Simvastatin, Atorvastatin etc.
• Statins inhibit HMG CoA reductase by competitive inhibition and reduce cholesterol levels.

Case 2

Despite dietary control, a 55-year-old man had elevated serum cholesterol. He was advised to take the tablet Simvastatin and three months later his cholesterol concentration was found to be normal.

Question 1. Name the enzyme of cholesterol biosynthesis which is inhibited by Simvastatin.
Answer:

• HMG CoA Reductase.
• Statins inhibit HMG CoA reductase by competitive inhibition and reduce cholesterol levels.

Question 2. Give the reaction catalyzed by this enzyme.
Answer:

Question 3. Name the precursor of Cholesterol synthesis– Acetyl CoA.
Answer:

2 acetyl CoA → Acetoacetyl CoA → Cholesterol.

Question 4. Name two products formed from cholesterol.
Answer:

1. Vitamin D
2. Bile acids
3. Steroid hormones

Covid-19

Case 1

A person who traveled from Wuhan city of China in February 2020 came to OPD with a chief complaint of fever, dry cough, and body aches for 6 days. He develops a lower respiratory tract infection and an X-ray showed ground-glass opacities and consolidation.

COVID-19

It is an infectious disease caused by a newly discovered coronavirus. Causative agent- SARS COV 2 (Severe acute respiratory syndrome Coronavirus 2)

COVID-19 Mode of transmission

It is transmitted through droplets generated when an infected person coughs, sneezes, or exhales. These droplets are too heavy to hang in the air and fall on surfaces. The person gets infected when he is nearby to COVID positive patient. It also gets infected by touching contaminated surfaces and then to the nose and mouth.

COVID-19  Incubation period– 2–14 days

COVID-19 Symptoms

1. Sore throat.
2. Fever.
3. Dry cough.
4. Fatigue.
5. Body ache.
6. Runny nose.
7. Diarrhea.

COVID-19 Phases of Disease

Phase 1– Appearance of disease in people with travel history.

Phase 2– Local transmission- infected patient with travel history spreads the disease to friends or close relatives (source of infection can be traced).

Phase 3– Community spread- when infection happens in public and the source of infection can’t be traced.

Phase 4– Epidemic in the country– A large number of people are infected with the disease in a region at a particular time.

Laboratory diagnosis– Real-time rt-PCR (reverse transcriptase Polymerase chain reaction).

Sample– Bronchoalveolar lavage fluid, nasal or throat swab.

COVID-19 Prevention

1. Social distancing– Maintain a safe distance from anyone who is sneezing or coughing
2. Wash your hands frequently– Use soap and water for more than 40 seconds.
3. Use alcohol-based sanitizer (> 70% alcohol) or hand rub when soap is not available.
4. Use a face mask and don’t touch your eyes, nose or mouth frequently.
5. Stay home.
6. In the pandemic– Isolation of COVID positive patient and quarantine of suspected patient is indicated.

COVID-19 Treatment

1. No definitive treatment is available to date.
2. Symptomatic treatment.
3. Hydroxychloroquine and azithromycin were found to be effective.
4. Antiviral drug trials are ongoing.
5. Plasma therapy showed some promising results.
6. A vaccine in the development phase.