Ep-PAINE-nym



Bence Jones Protein

Other Known Aliasesurine monoclonal globulin protein

Definitionimmunoglobulin paraproteins produced by neoplastic plasma cells that are found in the urine due to decreased kidney filtration from acute kidney injury

Clinical SignificanceBence Jones proteins are classically associated with multiple myeloma and Waldenström’s macroglobulinemia and these proteins were detected by heating a urine specimen to promote precipitation of the protein, but now is seen on electrophoresis of concentrated urine. Newer serum free light chain assays have been shown to be more sensitive and superior to the urine studies and are coming into favor.

HistoryNamed after Henry Bence Jones (1813-1873), who was an English physician and chemist and received his medical doctorate from St. George’s Hospital in 1840. His love for chemistry was sparked during his medical training and he simultaneously undertook private instruction in chemistry studies from professor Thomas Graham. After medical school, he went to Giessen, Germany to train under Justus von Liebig’s (the leading chemist of his time) at his animalistic chemistry school. He described his eponymous finding in 1847 in an article entitled “On a new substance occurring in the urine of a patient with Mollities Ossium”. His work on applying chemistry principles to human disease was so far ahead of his time that his work was not nearly as successful as it should have been due to the lack of knowledge of biochemistry and physiology of the time.


References

  1. Firkin BG and Whitwirth JA.  Dictionary of Medical Eponyms. 2nd ed.  New York, NY; Parthenon Publishing Group. 1996.
  2. Bartolucci S, Forbis P.  Stedman’s Medical Eponyms.  2nd ed.  Baltimore, MD; LWW.  2005.
  3. Yee AJ, Pfiffner P. (2012).  Medical Eponyms (Version 1.4.2) [Mobile Application Software].  Retrieved http://itunes.apple.com.
  4. Whonamedit – dictionary of medical eponyms. http://www.whonamedit.com
  5. Up To Date. www.uptodate.com
  6. Katzmann JA, Abraham RS, Dispenzieri A, Lust JA, Kyle RA. Diagnostic performance of quantitative kappa and lambda free light chain assays in clinical practice. Clinical chemistry. 2005; 51(5):878-81. [pubmed]
  7. Jones HB. On a new substance occurring in the urine of a patient with mollities ossium. Philosophical Transactions of the Royal Society. 1848;138:55–62. doi:10.1098/rstl.1848.0003

PAINE #PANCE Pearl – Hematology



Question

57yo Caucasian male presents to his primary provider with a one-year history of joint pain, weakness, and fatigue. He has a past medical history significant for hypertension and hyperlipidemia, for which he is being treated and is controlled on medications. His wife reports his skin has become a little darker over the last year as well. The rest of his physical examination does not reveal any abnormalities. Routine chemistries show a glucose of 214 mg/dL, AST of 472 mg/dL, and ALT of 513 mg/dL. What two (2) laboratory studies should be ordered next?



Answer

Hemochromatosis is at the top of the differential in a patient with elevated transaminases, heart disease, arthropathy, and hyperpigmented skin changes. As part of the initial screening, iron studies should be performed and an elevated transferrin saturation and serum ferritin are both elevated in hemochromotosis.


References

  • Bacon BR, Adams PC, Kowdley KV, Powell LW, Tavill AS, . Diagnosis and management of hemochromatosis: 2011 practice guideline by the American Association for the Study of Liver Diseases. Hepatology (Baltimore, Md.). 2011; 54(1):328-43. [pubmed]

Ep-PAINE-nym



Homan’s Sign

Other Known Aliasesdorsiflexion sign

Definitionpain in the posterior leg (classically behind the knee) with forced dorsiflexion of the foot

Clinical Significancethis examination finding was used in patients with a suspected DVT and before D-Dimers and clinical ultrasound were readily available. It is clinically useless as it has been studied extensively and found to have a sensitivity of 10-54% and specificity of 29-89%, thus not ruling in or out the condition consistently.

HistoryNamed after John Homans (1877-1954), who was an American surgeon and received his medical doctorate from Harvard Medical School. He worked with Harvey Cushing and Samuel Crowe early in career exploring the connection between the piuitary gland and the reproductive system. He first described his eponymous finding in 1944 in a NEJM article entitled “Diseases of the veins” and later published the first case report of a DVT occuring after prolonged sitting on a flight between Boston and Caracas in 1954. He was a founding member of the the Society for Vascular Surgery and the namesake of the John Homans Chair of Surgery position at Harvard Medical School and John Homans Fellowship in Vascular Surgery at the Brigham and Women’s Hospital.


References

  1. Firkin BG and Whitwirth JA.  Dictionary of Medical Eponyms. 2nd ed.  New York, NY; Parthenon Publishing Group. 1996.
  2. Bartolucci S, Forbis P.  Stedman’s Medical Eponyms.  2nd ed.  Baltimore, MD; LWW.  2005.
  3. Yee AJ, Pfiffner P. (2012).  Medical Eponyms (Version 1.4.2) [Mobile Application Software].  Retrieved http://itunes.apple.com.
  4. Whonamedit – dictionary of medical eponyms. http://www.whonamedit.com
  5. Up To Date. www.uptodate.com
  6. McGee, Steven (2012). Evidence-Based Physical Diagnosis. Philadelphia, USA: Saunders. pp. 472–473. ISBN978-1-4377-2207-9
  7. Homans J. Diseases of the veins. N Engl J Med 1944: 231; 51-60
  8. Homans J. Thrombosis of the deep leg veins due to prolonged sitting. The New England journal of medicine. 1954; 250(4):148-9. [pubmed]
  9. Barker WF. John Homans, MD, 1877-1954. Arch Surg. 1999;134(9):1019–1020. doi:10.1001/archsurg.134.9.1019

PAINE #PANCE Pearl – Hematology



Question

57yo Caucasian male presents to his primary provider with a one-year history of joint pain, weakness, and fatigue. He has a past medical history significant for hypertension and hyperlipidemia, for which he is being treated and is controlled on medications. His wife reports his skin has become a little darker over the last year as well. The rest of his physical examination does not reveal any abnormalities. Routine chemistries show a glucose of 214 mg/dL, AST of 472 mg/dL, and ALT of 513 mg/dL. What two (2) laboratory studies should be ordered next?

Ep-PAINE-nym



Schilling Test

Other Known Aliases – none

Definitionlaboratory test for pernicious anemia (specifically intrinisic factor deficiency) that led to vitamin B12 (cobalamin) deficiency. It involved ingesting a oral dose of radiolabeled vitamin B12 (to test oral absorption), an IM injection of vitamin B12 (to saturate liver stores), and a 24hr urine collection to see how much was absorbed and excreted. If intestinal absorption was intact (intrinsic factor present), then > 10% of the radiolabeled vitamin B12 would be in the urine.

Clinical SignificanceThis was the first and only test at the time to be able to diagnose pernicious anemia, but is now largely a test of historical interest only as better diagnostic studies have been developed.

HistoryNamed after Robert F. Schilling (1919-2014) an American physician and researcher who received his medical doctorate from the University of Wisconisn-Madison in 1943. Immediately after graduation, he joined the Pacific Front as a physician in the 3d Marine Division. After the war, he completed postgraduate training at Harvard before returning to Wisconsin to practice hematology. He studied extensively on the metabolism of vitamin B12 and the urinary excretion of radiolabeled vitamin B12 in pernicious anemia and in 1953, published a paper entitled “The effect of gastric juice on the urinary excretion of radioactivity after the oral administration of radioactive vitamin B12”, which would go on to be called the “Schilling Test”.


References

  1. Firkin BG and Whitwirth JA.  Dictionary of Medical Eponyms. 2nd ed.  New York, NY; Parthenon Publishing Group. 1996.
  2. Bartolucci S, Forbis P.  Stedman’s Medical Eponyms.  2nd ed.  Baltimore, MD; LWW.  2005.
  3. Yee AJ, Pfiffner P. (2012).  Medical Eponyms (Version 1.4.2) [Mobile Application Software].  Retrieved http://itunes.apple.com.
  4. Whonamedit – dictionary of medical eponyms. http://www.whonamedit.com
  5. Up To Date. www.uptodate.com
  6. Schilling RF. Intrinsic factor studies. 2. The effect of gastric juice on the urinary excretion of radioactivity after the oral administration of radioactive vitamin B12. J Clin Lab Med. 1953;42;860-866
  7. Schilling Test. Stat Pearls. 2018. https://www.ncbi.nlm.nih.gov/books/NBK507784/

PAINE #PANCE Pearl – GYN



Question

Polycystic ovarian syndrome (PCOS) can often be a clinical diagnosis due to the classic distinguishing features of hirsutism, obesity, menstrual irregularities, and infertility. What is the classic relationship between FSH and LH in a patient with PCOS?



Answer

The classic relationship between LH and FSH in PCOS is > 2.5:1.

LH secretion is elevated, while FSH secretion is the same, or even decreased. LH stimulates theca cell proliferation and secretion of androgens, but there is insufficient FSH to stimulate granulosa cells. Although this is classically seen, LH:FSH is NOT used in any diagnostic criteria for PCOS.