Podcast Episode 85: Ten Mixed Multiple Choice Questions

Answer: A. Cystic fibrosis

Cystic fibrosis (CF) commonly presents with meconium ileus, characterized by bilious vomiting, distended loops of bowel on radiography, and failure to pass meconium. CF is an autosomal recessive disease and is common in Caucasians. Neonates with CF commonly present with failure to thrive, respiratory compromise, and meconium ileus. In meconium ileus, abnormally thick meconium results in bowel obstruction, perforation, or volvulus. CF is diagnosed by the sweat chloride test or genetic testing. Radiography in ileus can demonstrate distended loops of bowel from the obstruction.

• Hirschsprung disease would present with abdominal pain with chronic constipation. There would be an absence of stool in the rectal vault on rectal exam and a positive squirt sign on physical exam (expulsion of stool/flatus on rectal exam).
• Jejunal atresia is characterized by the “triple bubble” sign on abdominal radiographs as well as bilious vomiting.
• Pyloric stenosis presents with non-bilious and projectile vomiting with a palpable mass on abdominal exam. This diagnosis can be confirmed with an ultrasound. The patient should first be rehydrated and have their electrolytes repleted prior to imaging.
• Tracheoesophageal fistula presents with coughing and choking with feeding. This breastfeeding and asymptomatic child in terms of his respiratory status suggests against this.

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The answer is B. Elevated IgG in the cerebrospinal fluid (CSF)

This patient’s clinical presentation is consistent with multiple sclerosis (MS), which is associated with an elevated IgG in the CSF.

MS is associated with oligoclonal bands on CSF evaluation in 80% of cases. The bands result from IgG overproduction, likely as a result of the autoimmune processes that occur in MS. Patients with MS frequently present first with symptoms of optic neuritis, which include loss of vision or blurry vision (usually unilateral), with severe pain with eye movement. The prognosis of MS differs drastically from patient to patient, but most commonly has a relapsing-remitting course.

Incorrect Answers:

• Mononuclear pleocytosis, not polycythemia, is associated with MS.
• MS plaque is hyperintense, not hypointense, on T2 FLAIR.
• MS is not associated with subdural hematomas. In addition, a subdural hematoma would be unusual in this young patient without a history of trauma.
• Small, punctate hypointensities on gradient-echo MRI is typical of diffuse axonal injury, which would be unlikely in this patient without a history of trauma.

Review NCCPA Blueprint Topic: Multiple sclerosis (ReelDx + Lecture)

The answer is D. Magnesium

This patient in this vignette demonstrates a constellation of findings related to the complications of hypomagnesemia. Although alcohol withdrawal may present with seizures, the constellation of brisk DTRs, weakness, and prolonged QT suggest hypomagnesemia. The treatment for this patient will be multi-faceted, with magnesium repletion a necessity.

Hypomagnesemia (<1.5 mg/dL) is a potentially serious condition that may be difficult to recognize due to non-specific manifestations. Mild signs of hypomagnesemia include: generalized weakness, fatigue, nausea and vomiting. As deficiency progresses patients may complain of numbness, cramping, and dysphagia. Physical exam findings may reveal increased DTRs and fasciculations. If hypomagnesemia is acute in onset and/or severe, patients may develop altered mental status, seizures, or cardiac conduction abnormalities. Low magnesium levels also have the potential to affect other electrolyte levels. In patients with hypomagnesemia it is not uncommon to see hypokalemia (K+ conductance changes increasing renal losses) and hypocalcemia (due to PTH resistance).

Incorrect Answers:

• This patient is likely hypokalemic secondary to hypomagnesemia. In fact, hypokalemia may contribute to the EKG findings. If the patient is solely hypokalemic, without any other electrolyte disturbances, DTRs will be decreased rather than increased.
• A patient with hypocalcemia may present in the same fashion as this patient (altered mental status, seizures, increased DTRs, and prolonged QT). While hypomagnesemia can lead to hypocalcemia, it is important to understand that a deficiency in magnesium itself can independently cause neuromuscular abnormalities. Seeing as this patient is malnourished and a chronic alcoholic, magnesium deficiency is the likely etiology.
• Folate deficiency is common in chronic alcoholics. It typically presents with macrocytic anemia without neurological complications
• Vitamin D deficiency is often asymptomatic but may present with signs of osteomalacia in adults and rickets in children.

Review NCCPA Blueprint Topic: Fluid and Electrolyte Disorders (PEARLS)

The answer is D. This mass will most likely decrease in size or disappear over time

This patient is a young female with a round, mobile mass that seems to respond to hormonal fluctuations, most likely a fibroadenoma, a benign mass common in reproductive-aged women. In adolescents, the majority of lesions will diminish or completely resolve over time, so only reassurance and observation are required. 

Classic fibroadenomas are relatively small (2-3 cm in size), in the upper outer quadrant of one or both breasts, and feel rubbery to palpation. They are generally painless but may become tender around the time of menses, as in this patient. There should be no skin changes, breast drainage, or lymphadenopathy. For an adolescent patient without concerning features or strong family history of premenopausal breast cancer in multiple first-degree relatives, there is no increased risk of malignancy from fibroadenomas. Fat necrosis is also a possible diagnosis in this softball player, as many patients do not recall a specific inciting trauma. However, given that the mass has been present for 2 months and undergoes hormonal changes, fibroadenoma is still the most likely diagnosis. Either way, the mass should eventually resolve and ultrasound is only indicated if the patient is older or there is persistence or change in the mass (Illustration A). Ultrasound is preferred in young women due to high breast density and the radiosensitivity of their tissues, but if the patient is over 35, mammography may also be performed. It would show a “popcorn” appearance (Illustration B). Upon confirmation of the diagnosis, either by imaging findings or core needle biopsy, surgical excision can be performed only if the patient experiences significant symptoms. Otherwise, routine follow-up is sufficient.

Incorrect Answers:

• Excision is usually not required for fibroadenomas given that they are not associated with increased risk of malignancy. If a patient feels the symptoms are too bothersome, surgical resection can be performed. If the diagnosis is called into question due to persistence or growth and there is concern for malignancy, excision may be required after imaging and biopsy are performed.
• Oral contraceptives containing estrogen may increase, not decrease, the size of the fibroadenoma. Since these tumors are hormonally receptive, they often grow and become tender around the time of menses, during pregnancy, and with estrogen administration (as in an OCP). For this reason, they also typically regress in menopause.
• Breast cancer risk is not increased by fibroadenomas, especially ones that are simple (no skin changes, drainage, lymphadenopathy, etc.), as in this patient. This patient’s family history of postmenopausal breast cancer in a second degree relative does put her at minimally higher risk of breast cancer, but this is unrelated to her fibroadenoma.
• A rapid growth to over 5 cm suggests that the mass is actually not a fibroadenoma but a phyllodes tumor (Illustration C). This is a rare neoplasm that can be benign or malignant, and although most phyllodes tumors occur in older women, they have been reported in patients as young as 10 years old. They are known for their rapid increase in size within weeks and any such growth should be evaluated with ultrasound and core needle biopsy (and mammography if the patient is over 35). Given the malignant potential, wide local excision is the standard of care. Chemotherapy and radiation are generally not indicated as effectiveness is unclear.

Review NCCPA Blueprint Topic: Fibroadenoma

The answer is B. Endometriosis

With endometriosis, the uterus is often fixed and retroflexed in the pelvis. The palpable mass is an endometrioma or “chocolate cyst”. The patient with endometriosis also often has dysmenorrhea, dyspareunia, and dyschezia.

Incorrect answers:

• It is important to consider ovarian cancer in a patient with a pelvic mass however, ovarian cancer usually occurs in older women over age 55 and patients are often asymptomatic until the disease is more advanced
• Functional ovarian cysts occur from ovulation and usually are not symptomatic.
• With PID the patient will have abdominal tenderness, adnexal tenderness, cervical motion tenderness, and elevated temperature.

Review NCCPA Blueprint Topic: Endometriosis (Lecture)

The answer is A. Median nerve

This clinical presentation is consistent with carpal tunnel syndrome (CTS), the most common entrapment neuropathy, caused by compression of the median nerve as it travels under the flexor retinaculum. During pregnancy, increased edema causes a narrowing of the carpal tunnel, which predisposes the entrapment of the median nerve. The median nerve is responsible for sensory and motor distribution of the thumb, index, middle and radial half of the ring finger. Hallmark symptoms of CTS include numbness and paresthesias in the median nerve distribution. Weakness and atrophy of the thenar muscles may be evident if CTS is left untreated.

Incorrect Answers:

• The ulnar nerve supplies sensory innervation to the 5th digit and the medial half of the 4th digit and motor innervation of the forearm flexors, and several intrinsic muscles of the hand. The ulnar nerve is most commonly injured at the elbow as it courses adjacent to the humeral medial epicondyle or it may be compressed between the two heads of the flexor carpi ulnaris muscles (cubital tunnel syndrome).
• The radial nerve supplies the medial, lateral, long heads of the triceps brachii, 12 muscles in the posterior compartment of the forearm and the associated joints and overlying skin. Radial nerve injury may result from spiral fracture of the midshaft of the humerus and result in “wrist drop”
• The axillary nerve supplies the deltoid, teres minor, and the long head of the triceps brachii. Axillary nerve injury may result from dislocation of the head of the humerus
• The anterior interosseous nerve branch of the median nerve supplies the deep muscles on the anterior of the forearm. This includes the flexor pollicis longus, pronator quadratus, and the radial half of flexor digitorum profundus

Review NCCPA Blueprint Topic: Carpal Tunnel Syndrome

Answer: A. Timolol ophthalmic solution

Acute angle-closure glaucoma, also known as narrow-angle glaucoma, presents with sudden onset blurry vision, hardened eyeball, and increased IOP. First-line emergency treatment includes alpha 2 selective adrenergic agonists, beta-blockers, or carbonic anhydrase inhibitors. Acute angle-closure glaucoma is caused by relative pupillary block of aqueous humor as it flows from the posterior to the anterior chamber through the iris-lens channel (the canal of Schlemm). Sudden attacks are more likely to occur when the pupil is partially dilated, for example, being in a darkened room such as a movie theater, or when eye drops are taken that dilate the pupil. If not treated immediately, it can damage the optic nerve and result in permanent vision loss within hours. Risk factors include certain medications (dilating drops, anticholinergic, antidepressants).

Incorrect Answers:

• Epinephrine would cause pupil dilation which would worsen acute angle glaucoma.
• Laser peripheral iridotomy is an appropriate and definitive treatment for acute angle glaucoma in the post-acute phase of treatment once IOP is controlled.
• Anticholinergics would cause pupil dilation which would worsen acute angle glaucoma
• NSAID ophthalmic solution can theoretically worsen acute angle glaucoma because of its anti-prostaglandin effect.

Review NCCPA Blueprint Topic: Glaucoma (Lecture)

The answer is B: Chest CT scan

The patient presents between the ages of 55 and 80 and has quit smoking within the last 15 years. She should undergo an annual low dose chest CT scan for lung cancer screening.

Cigarette smoking is the leading cause of preventable death in the United States and significantly contributes to deaths from cancer along with cardiovascular and pulmonary diseases. Smoking not only harms adults but also results in the deaths of about 1,000 infants annually. The USPSTF report on the guidelines for lung cancer screening states that age, total cumulative exposure to tobacco smoke, and years since quitting smoking are the most important risk factors for lung cancer. They report that annual screening for lung cancer with low-dose CT in a defined population of high-risk persons can prevent a substantial number of lung cancer–related deaths as evidenced by large randomized controlled trials.

Incorrect Answers:

• An abdominal ultrasound is recommended for men between the ages of 65 and 75 who have ever smoked, but this recommendation does not hold for women
• The patient does not require a pap smear because she is older than 65 and does not have a history of cervical or endometrial malignancy, and all of her previous pap smears have been negative.
• The patient should next get her colonoscopy at age 72 since her last colonoscopy was at age 62 and was normal
• The patient does not have any acute respiratory or pulmonary problems and therefore does not need a chest radiograph

Review NCCPA Blueprint Topic: Substance-related and addictive disorders (ReelDx)

The answer is A. Chlamydia trachomatis

This patient is presenting with a tender urethra with a discharge and a negative Gram stain suggesting a diagnosis of urethritis from Chlamydia trachomatis.

Urethritis in men presents with dysuria and urethral discharge with numerous neutrophils on urethral swab. Urethritis in men is most commonly caused by 2 categories of sexually transmitted infections. In gonococcal urethritis, patients present with purulent discharge and gram-negative diplococci on Gram stain, with N. gonorrhoeae as the offending agent. In nongonococcal urethritis, patients present with watery discharge which shows no bacteria on Gram stain (it is intracellular). Chlamydia is the most common offending agent in nongonococcal urethritis and is the most common cause of urethritis overall. Azithromycin is a good choice for the treatment of nongonococcal urethritis because it covers Chlamydia and other common causative organisms. It is often given with ceftriaxone which offers double coverage for N. gonorrhoeae.

Incorrect Answers

• Escherichia coli is the most common cause of cystitis which presents with dysuria and leukocytes, bacteria, and nitrites on urinalysis. TMP-SMX is a first-line agent for the treatment of uncomplicated cystitis.
• Neisseria gonorrhoeae is the most common cause of gonococcal urethritis which presents with a purulent urethral discharge and gram-negative diplococci on Gram stain. Ceftriaxone (a single injection) is the most common treatment for gonococcal urethritis. Ceftriaxone would be appropriate if the patient presented with purulent urethral discharge and a supportive Gram stain. Patients treated for gonococcal urethritis are generally treated for a Chlamydia trachomatis infection since there is a high rate of co-infection.
• Staphylococcus saprophyticus is a common cause of UTI in young and sexually active women. It is still less common a cause of a UTI when compared to Escherichia coli.
• Trichomonas vaginalis is a less common cause of male urethritis. It can present with pruritus but with less specific symptoms when compared to women with this condition. If the patient did not respond to antibiotics, this diagnosis could be suspected. Metronidazole is the treatment of choice.

Review NCCPA Blueprint Topic: Chlamydia (Lecture)

The answer is B. Fragmented red blood cells

The boy in this vignette most likely has hemolytic uremic syndrome (HUS), which is characterized by microangiopathic hemolytic anemia with schistocytes.

HUS usually occurs in children and is caused by an E. coli 0157:H7 infection. The classic presentation follows an acute diarrheal illness. HUS is characterized by microangiopathic hemolytic anemia, thrombocytopenia, and renal failure. The presentation is similar to thrombotic thrombocytopenic purpura (TTP) but without the fever and neurologic symptoms. The key differentiating factor, in this case, is diarrhea + elevated BUN. Keep in mind that in HUS uremia is elevated to a greater extent than TTP. On the other hand, TTP presents with more neurologic signs, and will not be preceded by diarrhea on the PANCE exam.

Incorrect Answers:

• Rouleaux (stacked RBCs) are seen most notably in multiple myeloma. As well as many other hyperviscosity syndromes. This finding is highly non-specific.
• Spur cells are seen with liver disease.
• Giant platelets are seen in idiopathic thrombocytopenic purpura (ITP) as well as Bernard-Soulier syndrome.
• Schistocytes would be expected in HUS.

Review NCCPA Blueprint Topic: Infectious Diarrhea (ReelDx + Lecture)