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* CCS answers !!
 #157724  
  levo - 01/31/07 13:06
 
  Hi guys, I found these somewhere I don't remember, they are the answers to the CCS cases that come with step 3 CD, unfortunatly I don't have the first case but I found it very helpful and I thought you might too.

Case #2: 32-year-old black woman with pain and swelling, right knee
Case Introduction: Essential Facts
Patient is black, 32 years old
She has a one-week history of knee pain (right)
She comes to the office

Comments
Pain and swelling of the knee developed gradually over a period of one week. This is unlikely to be due to trauma. The differential diagnoses are too many to be listed here, so let’s learn more about the patient first.

Initial Vitals: Essentially normal

Initial History: Essential facts
• Symptoms began 2 months ago with fatigue and generalized weakness
• Followed by generalized body aches, prolonged early morning joint stiffness, pain and occasional swelling in both wrists
• Her symptoms are moderately severe, not responsive to mild analgesics
• She does not engage in unsafe sexual practices

Possible differential diagnoses at this stage include:
• Systemic lupus erythematosus (SLE)
• Rheumatoid arthritis
• Gonococcal arthropathy
• Reiter’s syndrome
• Osteoarthritis

Comments
Gonococcal arthropathy is unlikely (though remotely possible) because of her history. It is more likely in patients who engage in unsafe sexual practice4s, or those with multiple sexual partners. Osteoarthritis (OA) is also unlikely because of the duration of the stiffness. The stiffness of OA generally resolves after a few minutes, up to a maximum of 30 minutes. Reiter’s syndrome is more common in men, is associated with urethritis, uveitis and arthritis. However, this patient has neither urethral nor eye symptoms, so this differential is also unlikely. We are now left with SLE and RA.
The next step is to perform physical examination. Click the Interval History and PE button on the left side of the screen, and check the following regions under Physical Examination:

• General Appearance (almost always necessary)
• Skin (Reiter’s disease has skin manifestation)
• Chest/Lungs
• Heart Cardiovascular
• Abdomen
• Extremities
• Genitalia

Comments
Notice that we are taking our time with the physical examination. This is because the patient presented to the office, and her situation is not life threatening, so we can afford to take our time for proper examination.

Physical Examination: Essential Findings
• Bilateral warmth and swelling, both wrists and knees
• Rest of examination normal

From the foregoing, it is clear that we are dealing with rheumatoid arthritis. Let’s now proceed to treatment. Click the Write Order button, and enter each of the following (one per line):

• X-ray (knee, wrist, routine (you can choose both by pressing Ctrl in Windows, and selecting both knee and writs x-rays)
• ESR (routine)
• Complete blood count (with differentials). Routine
• Rheumatoid factor (routine)
• Antinuclear antibody (ANA) titer, serum

Comments
Notice that there are two choices for ANA. The first choice is ANA, serum, and the second, ANA titer, serum. ANA serum only measures the presence of ANA, while the other test quantifies the amount present in the serum, if any. We are more interested in knowing how much of ANA is in the serum, so we choose the second test.
Also, note that it will take a total of six hours before all the results of these tests are available. That means we must proceed with treatment even before we see any of the results. The patient cannot sit still for six hours, untreated, while we await the results of the lab tests. Let us start with arthrocentesis. We would like to drain some fluid from the swollen knee joint. Click the Order button at the bottom of the screen and enter the following orders:

• Arthrocentesis (confirm your choice by advancing clock for 20 minutes)
• On the joint fluid drained from the knee, order the following tests:
• Crystals (routine) rule out gout
• Cell count (routine) rule out infections
• Culture joint fluid (routine)
• Gram stain (synovial fluid is closest). Order this stat.

All the tests have now been sent to the lab. We can obtain the result of gram stain within 20 minutes. Let us advance the clock, so that this result will become immediately available.
Click on Obtain Results and see patient in 20 minutes. The result of gram stain is displayed (normal in this case). We can now continue with further treatment.
Click Order button at the bottom of the screen and enter:

• Ibuprofen (oral, continuous)

Patient may go home, for re-evaluation with results the next day.
FAQ: Since we are fairly certain that this patient has RA, why can’t we just start steroid treatment right away?
Answer: The big question is, what would happen to this patient if we wait to confirm our suspicions? Nothing! Remember, you are expected to manage each patient in the most standard manner possible. It is not standard practice to begin treatment of cold cases without confirming the diagnosis.
Schedule an appointment for the patient for the next day (Click See patient Later button, select See Patient In and enter 1 in the day column on the right). Continue to advance the clock until you see the results of the tests done earlier.

Lab and Radiological Results: Essential Findings
• X-ray, knee: inflammatory arthritis
• No crystals in synovial fluid
• Cell count, synovial fluid: 14,000 wbc/cmm, 35% polymorphs
• ESR: 47 mm/hr
• CBC: Normal
• Rheumatoid factor (RF): moderately high
• ANA: Negative

Our next move is to do interval follow up, and check the patient’s extremities. Click Interval History, and select Interval/Follow up, Extremities. The results are essentially unchanged from before. Meanwhile, our results have confirmed rheumatoid arthritis (RA) as the cause of the patient’s pain. Let us start the patient on prednisone.
Click the Order button and enter

• Prednisone (oral, continuous)

Advance the clock by 1 day, so that we can see a lab result. Culture result is normal. Perform interval follow up once more, and examine the extremities. The results have not changed much. Since we are sure that our treatment is right, we will make no changes at this time. Give the patient an appointment for 4 or 5 days. When she arrives, take an interval history and perform an interval physical examination. The patient now feels better than before. She will continue her treatment as before, and see us in 14 days. Book her an appointment for 14 days. When she arrives, perform the appropriate assessment. You will discover that she now feels much better. Slight swelling persists. Let her continue her medication, and see us again in 14 days.
At this stage, the case is about to end. We may discontinue ibuprofen, since there is no need for it at present. On the other hand, we may let her continue with it.

Final diagnosis: Rheumatoid Arthritis

End of case.



SUGGESTED SOLUTIONS TO THE RELEASED CCS PRIMUM CASES
Important Notice
The five primum cases released by the USMLE are copyrighted materials, and we cannot reproduce them here. We strongly encourage you to download and install the questions on a computer system so that you can follow the management steps as we go along.
Our solutions to these items consider the standard of care that is prevalent at the time of writing. We have made every efforts to ensure that sufficient explanations are given for the management actions taken at various times during the solution. You should bear in mind however, that these are suggested solutions. The same cases may be managed in a variety of ways. If you have different ideas than the ones here, that is fine. We believe though that you will find these helpful.

How to Use this Guide
We suggest that you print out this guide, so that you can have it on hand when you are practicing the questions.
Good luck in your exams.


Case #3: 5-year-old boy with recurrent nosebleeds
Initial History: Essential Facts:
• 5-year-old white boy
• Upper respiratory tract infection 2 weeks previously, successfully treated with acetaminophen and pseudoephedrine
• Recurrent nosebleeds for 24 hours, now unresponsive to direct pressure
• Purpuric lesions on legs for 24 hours
• No history of falls, no family history of abnormal bleeding, no previous history of similar problems
• Appetite good; no signs of systemic infection

Comments
Recent onset of nosebleeds and presence of purpuric lesions point to problems with coagulation. Good appetite and absence of systemic signs of infection are good signs.

Initial vital signs: essentially normal

Differential diagnoses at this stage:
• platelet disorders (e.g immune thrombocytopenic purpura)
• clotting factors disorders
• blood vessel disorders

Comment
Platelet disorders tend to cause bleeding into the skin and mucous membranes; clotting factor disorders would be expected to cause more deep seated bleeding (e.g. into joints, hematomas).
Because the abnormal bleeding is of recent onset, vascular disorders are unlikely. Clotting factors are not likely to be the cause of bleeding either, because this patient has not had similar problems in the past.
The presence of purpura together with a recent history of (?viral) respiratory illness will make us consider platelet disorders. Idiopathic thrombocytopenic purpura (ITP) is a strong differential at this stage.
Let us begin the management of the patient.

Initial Orders:
• Nasal packing
• CBC
• Prothrombin time (PT):
• aPTT (activated partial thromboplastin time)
• Serum Electrolytes
• BUN
• Serum Creatinine
• Group and screen blood (patient might need transfusion later; let’s get serum ready)
• Bleeding time (optional; see below)

Comment
We began with nasal packing because the patient is bleeding right now. This should relieve his anxiety for a time. Complete blood count (CBC) was ordered because we are considering platelet disorders as a possible cause of the patient’s problems. CBC will help us determine the platelet count. PT measures the integrity of the extrinsic and common pathways of the coagulation system, while aPTT helps us determine the intactness of the intrinsic and common pathways.

Advance the clock by 10 minutes (not rigid; you may use 5 or even 15 minutes, if you choose) to review the patient’s condition
Click on interval history and HEENT examination. You receive a message that patient is feeling better
Advance the clock to the next available result
Platelet is lowour initial suspicion of thrombocytopenia is confirmed. Let us order treatment.
By now we know pretty much that this patient most probably has ITP. The most appropriate treatment for this condition is corticosteroids.

Order treatment:
• Prednisone, oral continuous
• Write consult to pediatric hematologist
• Routine, probable ITP
• Reorder CBC 1 time routine (repeat for the day, subsequently 12 hourly)
• Admit to the ward
Diagnosis: ITP
Discharge on prednisone when platelet is 50,000+ (bleeding unlikely then), and review again after a few days (say, 1 week) for a repeat determination of the CBC. It should be well close to normal.



SUGGESTED SOLUTIONS TO THE RELEASED CCS PRIMUM CASES
Important Notice
The five primum cases released by the USMLE are copyrighted materials, and we cannot reproduce them here. We strongly encourage you to download and install the questions on a computer system so that you can follow the management steps as we go along.
Our solutions to these items consider the standard of care that is prevalent at the time of writing. We have made every efforts to ensure that sufficient explanations are given for the management actions taken at various times during the solution. You should bear in mind however, that these are suggested solutions. The same cases may be managed in a variety of ways. If you have different ideas than the ones here, that is fine. We believe though that you will find these helpful.

How to Use this Guide
We suggest that you print out this guide, so that you can have it on hand when you are practicing the questions.
Good luck in your exams.


Case #4: 25-year-old male patient with three-week history of diarrhea
Initial History: Essential Facts:
• Three week history of mucoid, non-bloody diarrhea
• Has prolonged diarrhea (three weeks)
• There is associated abdominal cramps

Comments
Diarrhea wakes patient up, meaning it is a non-functional diarrhea; functional diarrhea will not wake patient up. It is of recent onset, so irritable bowel syndrome is unlikely. Diarrhea is mucoid, so there is an infectious etiology; it is non-bloody, so there is no invasiveness of the GI tract.

Differentials at this time include:
• Infectious diarrhea (e.g. Giardiasis)
• Dysentery
• Inflammatory bowel disease

Giardiasis is one of the commonest causes of diarrhea in the adult population
Let us go on to perform the physical examination. We are interested in the following systems
Physical Examination:
• General appearance
• Abdomen/rectum
• Extremities
• Cardiovascular system
• Skin
• Lungs

Confirm your choice of PE. Afterwards, click on the Order button to place the following orders.

• Electrolytes
• BUN/ Creatinine
• CBC statim
• Stool for ova and parasites, C/S, clostridium
• Serum amylase and lipase to rule out Pancreatitis. Amylase is sensitive but not specific; lipase is specific but not sensitive
• Abdominal X-ray to rule out toxic megacolon/perforation, acute series

Comments
We have done everything we can do at this stage. Let us advance the clock to see the next available result. What we do next will be determined by what we get from the lab results. Advance the clock until you get the results:

Ova and parasite: positive for Giardia lamblia

Now that our diagnosis is confirmed, it is time to treat the patient. Click the Order button below the screen and order

Flagyl oral, continuous
We can now schedule an appointment for the patient. Let us see him in 1 week for follow-up.

Diagnosis: Giardiasis

End of case


SUGGESTED SOLUTIONS TO THE RELEASED CCS PRIMUM CASES
Important Notice
The five primum cases released by the USMLE are copyrighted materials, and we cannot reproduce them here. We strongly encourage you to download and install the questions on a computer system so that you can follow the management steps as we go along.
Our solutions to these items consider the standard of care that is prevalent at the time of writing. We have made every efforts to ensure that sufficient explanations are given for the management actions taken at various times during the solution. You should bear in mind however, that these are suggested solutions. The same cases may be managed in a variety of ways. If you have different ideas than the ones here, that is fine. We believe though that you will find these helpful.

How to Use this Guide
We suggest that you print out this guide, so that you can have it on hand when you are practicing the questions.
Good luck in your exams.


Case #5: 65-year-old white woman with left-sided chest pain

Initial History/Vital Signs:
• 65-year-old white woman with left-sided chest pain
• Anxious and sweating
• Has tachycardia and tachypnoea, with bounding pulses
• Severely hypertensive

Comment
Acute onset of sharp chest pain that radiates to the back in a hypertensive woman in the 7th decade of life makes aortic dissection very likely. We must proceed rapidly.

Differential diagnoses at this time would include:
• Aortic dissection (top on the list)
• Myocardial infarction
• Musculoskeletal pain
• Pneumothorax
• Costochondritis

Comments
As stated above, there is little doubt that this patient has aortic dissection. A close differential would be myocardial infarction. Chest pain not made worse by breathing indicates that the pleural is not involved, and neither is it a result of In any case, we need to address her problems without delay. Our next move is physical examination. Click the appropriate buttons and select the following:

• general appearance (remember case #1? You must always examine the patient’s general appearance)
• skin
• chest/lungs
• cardiovascular system
• abdomen
• extremities

Comment
The major findings are in the cardiovascular system. Bounding pulse with decrescendo murmur poiint to aortic incompetence. These findings lead us more towards dissection of the aorta. We need to quickly order laboratory investigations. Appropriate investigations to order now:

• 12-lead ECG stat.
• Chest X-ray (AP, portable)
• cardiac enzymes
• pulse oxymetry (if low then request ABG)
• CT scan of chest

Comment
As a rule of thumb, all patients with chest pain should have the above investigations done. a 12-lead ECG helps us rule in or out the heart as the cause of her chest pain. Portable chest x-ray can be rapidly done right in the ER.
Without waiting for the results of these investigations, we will now start treatment:
Click on the order button and enter the following orders, one per line

• morphine, intravenous, continuous
• phenergan, I/V, continuous (Antiemetic)
• oxygen by inhalation
• atenolol I/V bolus for elevated blood pressure

Comment
Morphine is for pain; phenergan is an anitemetic (emesis is a common side effect of morphine)
We have done what we can do for the patient for now. Let us find out how our patient is doing. We are going to take interval history.
Click on Interval Hx/PE and select

• Interval/Follow up
• Chest/lungs
• Heart/CVS

We discover that oxygen saturation is 96% (acceptable; ABG not needed at this time). Otherwise, no change in patient's condition.
We will now advance the clock to see patient with next available result:

ECG shows sinus tachycardia and left ventricular hypertrophy

Comment
This effectively rules out myocardial infarction. We still need to review the result of serum cardiac enzyme determinations, though.
The patient has received only partial relief. Click ok to continue. We need more results before we can make managemenbt decisions.
Keep on advancing the clock.

• X-ray result shows mediastinal widening
• CT scan shows ascending aortic dissection
• Patient's blood pressure improves.

We must now send a consult to the specialists.
Click the order button and order:

• consult to cardiovascular surgeons (reason: probable aortic dissection)
• consult to cardiologists (reason: probable aortic dissection)

Click on the Change Location button to the right of the screen to move patient to the ICU. Confirm move

• Take interval/follow-up history
• Examine chest & cardiovascular system
• order atenolol PO continuous (if BP remains high)

Patient is now feeling better. We need to get some laboratory results. Advance the clock to next available result
Cardiac enzyme comes back, ruling out MI. BP is now within normal range.
We must discontinue some of her antihypertensive medications, lest she becomes hypotensive.
Click on Triamterine once. Confirm cancelation. We may leave her on atenolol and thiazides.

Final diagnosis: Ascending aortic dissection

End of case


 
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* Re:CCS answers !!
#640860
  turtle - 01/31/07 13:10
 
  thank u, thanku , thanku , thanku ......................  
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* Re:CCS answers !!
#642399
  dr35 - 02/01/07 13:31
 
  thankyou  
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* thakyou
#642773
  aandi - 02/01/07 18:32
 
  thankyou levo it was very helpful,i am trouble with using the ccs .
this helped me a lot.

can you please add some information reg how to proceed in usung software for different cases.i will appreciate if you can offer help to me by phone.if you send the number by mail i will call you.

my email id tirounilacandin@gmail.com

thankyou
 
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