By John Hwang MD, Cindy Fang MD, Neha Sathe MD, Michael P. Janjigian MD || Audio Editing and Graphic by Amy Ou, MD
- Part 1 Case (2:05)
- Framing bias (7:07)
- Data-driving reasoning (11:48)
- Hypothesis-driven approach (12:38)
- Periodic paralysis syndromes (16:08)
- Representativeness heuristic (17:26)
- Part 2 Case (20:51)
- Pivot Points (31:36)
- Diagnosis (35:55)
- Take aways (37:20)
- A clinician employing “data-driven reasoning” (“working forwards”) starts with raw clinical data and tries to arrange them into meaningful patterns to build hypotheses about the patient’s illness.
- A clinician employing “hypothesis-driven reasoning” (“working backwards”) starts with a clinical problem, generates a series of hypotheses about the patient’s illness, then tests each of these against the available clinical data.
- Patients with hypokalemic periodic paralysis syndromes suffer episodic weakness due to massive intracellular shifts of potassium, often triggered by periods of stress or exercise; they can be entirely asymptomatic between episodes.
- The representativeness heuristic is a mental shortcut in which a clinician judges the probability of a diagnosis based on the similarity of the patient to the clinician’s mental picture (i.e. stereotype) of that diagnosis.
- Base-rate neglect refers to the tendency of clinicians to rely on information specific to a case (e.g. using the representativeness heuristic) to judge the likelihood of a given diagnosis, while ignoring the actual prevalence of that diagnosis.
- It is not uncommon for patients with Sjogren’s syndrome to develop renal manifestations of their disease; this can take the form of subclinical lab abnormalities, nephrogenic diabetes insipidus, progressive renal insufficiency, and chronic tubular or interstitial nephritis, with or without renal tubular acidosis.
- The combination of hypokalemia and non-anion gap metabolic acidosis is a diagnostically meaningful pattern, characteristic of two disease processes: diarrhea and renal tubular acidosis.
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- Zayac A, Shah R, Shah M, Umar J, Bansal N, Dhamoon A. Thyrotoxic hypokalemic periodic paralysis. QJM: monthly journal of the Association of Physicians 2016;109:613-4.
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- Francois H, Mariette X. Renal involvement in primary Sjögren’s syndrome. Nat Rev Nephrol. 2016 Feb; 12(2):82-93.
- Kronbichler A, Mayer G. Renal involvement in autoimmune connective tissue diseases. BMC Med. 2013; 11(95).