A 46-year-old man presents to the Emergency Department with headache and confusion. His medical history is significant for diabetes mellitus and chronic liver disease. Physical examination reveals a temperature of 39.3°C, nuchal rigidity, and dark skin pigmentation. He is admitted and a lumbar puncture is performed. The results of CSF analysis are shown below.
A gram stain of the CSF is negative.
Which of the following is likely responsible for this patient’s symptoms?
Listeria monocytogenes. The history of diabetes and liver failure with darkened skin on examination should raise suspicion for hemochromatosis, which commonly presents around this age in men. Patients with iron overload disorder are at higher risk of iron-loving organisms (e.g., Listeria, Vibrio vulnificus), and so meningitis should raise concern for this organism. The CSF findings are consistent with bacterial meningitis (low glucose and high protein), and like TB it can cause a lymphocytic pleocytosis. Because Listeria is an intracellular organism, gram staining is often negative; if positive, it will show gram-positive rods. The empiric antibiotic regimen for this patient should therefore include ampicillin to cover Listeria meningitis.
A 67-year-old man comes to the hospital after fainting while jogging. This was the first time this has happened, although he has been feeling dizzy and short of breath during exercise for the past several months. ECG shows left ventricular hypertrophy, and an echocardiogram shows extensive calcification of the aortic valve. He is subsequently scheduled for a valve replacement.
What other study should be ordered prior to surgery?
Coronary angiography. Prior to aortic valve replacement surgery, every patient should have his or her coronary arteries evaluated in case there is a need for CABG at the same time as the valve replacement surgery. (A, C) Cardiac stress testing would be helpful in diagnosing coronary artery disease, but the standard of care for an aortic valve replacement is to bypass the stress test in favor of angiography due to its superior accuracy. (D, E) The patient’s symptoms can be attributed to his valvular disease rather than a neurologic process.
A 52-year-old man presents to his primary care physician complaining of painful red bumps on his legs and muscle pain. On review of systems, the patient endorses weight loss over the last few months due to abdominal pain after eating. He has also noticed a slight limp. Physical examination is notable for erythematous tender nodules and palpable purpuric lesions predominantly over his lower extremity as well as a reticulated pattern of skin discoloration. He has a small decrease in strength and sensation in his right foot compared to his left.
Which of the following tests should be performed next to best identify the cause of this patient’s symptoms?
Tissue biopsy of skin lesions. This patient presents with symptoms of polyarteritis nodosa (PAN), which is diagnosed with a biopsy of an involved organ. (A) A positive ANCA is unlikely to be found in PAN and suggests an ANCA-positive vasculitis. (B, C) Although serum BUN to creatinine ratio and ESR are likely to be abnormal in patients with PAN, these tests are not specific. (E) A chest x-ray is used to rule out PAN as lung involvement is rare and positive findings suggest a different vasculitis.
A 23-year-old woman presents to the clinic with complaints of vague joint pains and a chronic rash on her face for the last year. She does not take any medications and uses no vitamins or supplements. She denies any known allergies. On examination, her temperature is 37.0°C, blood pressure is 130/80 mmHg, and heart rate is 70 beats per minute. Raised and scar-like circular red plaques are visible on her nasal bridge, pinnae, and neck in various stages of resolution. There is visible scarring and depigmentation in the central area of most lesions with a peripheral rim of hyperpigmentation. Her laboratory results are shown below.
Which of the following tests is most likely to be positive in this patient?
RPR. This question describes the discoid rash of SLE. This rash, in addition to vague joint pains, anemia, thrombocytopenia, leukopenia, and a positive ANA, makes SLE the most likely diagnosis. SLE is typically confirmed with the anti-dsDNA antibody or anti-Smith antibody. RPR and FTA/ VDRL, which are tests for syphilis infection, are often positive in SLE. (A) The presentation and positive ANA indicate SLE, not HIV infection. Anti-smooth muscle antibodies (for autoimmune hepatitis), the heterophile antibody test (for EBV infection), and the osmotic fragility test (for hereditary spherocytosis) would be unlikely to be positive in this patient. (C) Druginduced lupus is confirmed with positive anti-histone antibodies; however, this patient does not take any medications. (D) Anti-centromere antibodies are often seen in limited systemic sclerosis (CREST syndrome).
A 48-year-old woman presents with a rash (Figure below) and progressive difficulty in reaching for objects in cabinets and lifting her arms to brush her hair. Laboratory values indicate a creatine kinase (CK) of 1,400 U/L.
In addition to corticosteroids, what is the most appropriate next step in management?
Screen for malignancy. This patient’s presentation is consistent with dermatomyositis, which may present as a paraneoplastic syndrome. Both patients with dermatomyositis and polymyositis typically present with symmetrical proximal muscle weakness most commonly involving the shoulders but may also involve the pelvic muscles (difficulty rising from a chair). They both may have elevated CK, positive ANA, or positive anti-Jo-1 antibodies. However, patients with dermatomyositis will also present with a dermatologic finding such as a heliotrope rash, malar rash, or Gottron papules (Figure 12-11). Muscle biopsy will demonstrate perifascicular atrophy. Though there is an association with malignancy in both dermatomyositis and polymyositis, the risk is greater with dermatomyositis.
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