Episode 25: When Collagen Fails…
Author: Adam Md Kamal
Editor: Dr. Suneet Sood
Narrator(s): Adam Md Kamal
Imagine this: you are halfway through your pediatric rotation and you are about to complete your first year of houseman-ship. You have already seen your fair share of extraordinary cases: patients with Down’s Syndrome, Alagile Syndrome and Marfan syndrome. But today, in the busy pediatric clinic, a 5 year old boy has come in with his mother. Today, your knowledge is about to be tested.
The 6-year old boy, Alfred is a rather thin and feeble looking boy. His mother, Julia has brought him in with a set of complaints. He easily bruises even after minor falls, explains Julia. She shows to you several bruises all over the body including his legs and arms, all at various stages of healing. “Something’s not right,” you think to yourself. You continue listening to Julia who reveals that he has dislocated his shoulders two times. When asked further, you are surprised to find out that this has happened twice, on each side.
You’re curiosity has peaked; how could a 6-year old have dislocated his shoulder 4 times in total and bruises all over the body? Could this be a case of Non-Accidental Injury (NAI). In other words: abuse? Your mind is racing, thinking of a list of possible abusers. You even begin to suspect Julia. You begin to distrust her more and more as she begins talking about Alfred’s social history. Your distrust gets the better of you; just as you reach the phone to call your supervisor to inform him of an NAI, the door opens. And there he is your supervisor, Dr Alex, a senior pediatrician. “Go on…tell us more” Dr Alex says. He had been listening to the history intently outside the room and you notice he is just as interested as you, if not more.
After further discussion, you notice that the only thing that stands out in Alfred’s history is the frequent shoulder dislocation and multiple bruises. The birth, immunization and drug history are all normal. The social history also seems normal, but you know better: in a case of NAI, you are to remain vigilant and not take the information at face value as even Julia can be the source of abuse. But Julia also mentions that a relative once told her that the child might have Marfan syndrome because Alfred appears quite lanky and his joints were strangely flexible so she is worried he might have Marfan syndrome. Dr Alex who had been listening intently then begins a physical examination and asks you to write down the findings which he says aloud during the examination.
“Crowded oropharynx….hyper-extensible joints……..flat feet. Yes, I can see why you’re worried about Marfan Syndrome” Dr Alex tells Julia. He continue saying aloud results of physical examination”….multiple bruises covering the legs and arms…have you got all that down?” Dr Alex’s asks you as he ends the physical examination. You nod reassuringly. “So what do you think this is?” he asks you. This time you shrug your shoulders, signalling your sheer cluelessness about reaching a medical diagnosis. “Take a guess” Dr Alex commands you. You look at the notes you wrote in Alfred’s file: Multiple bruises, multiple bilateral shoulder dislocations, flat feet, hyper-extensible joints. You think to yourself and blurt out an answer, which sounded more like a question “Marfan syndrome with possible abuse.”
Dr Alex shakes his head with clear disagreement and begins to explain his diagnosis, both to you and Julia:
“Right, so I think what Alfred has is a disease called Ehlers-Dahnlos Syndrome. I can see why you are worried that it could be Marfan syndrome because both conditions are quite similar. In Marfan Syndrome there is a defect in fibrillin (1) which causes the joint anomalies, heart problems and tall stature” Dr Alex pats you on the back, clearly signalling that he understood why you thought it was Marfan Syndrome. Dr Alex continues, “Although in people with Ehlers Dahnlos would also have joint hyper-mobility, the problem isn’t with fibrillin; the problem is with collagen. There are many types of collagen, all found in various parts of the body. In EDS, type III collagen is defective (2). A defect here causes many problems with blood vessels that make them weak and they tend to rupture and bleed easily. That’s why young Alfred here has bruises everywhere in different stages of healing which on the surface, may appear to be abuse”. Dr Alex then gives you a reassuring look, signalling he understood your concerns of NAI. He continues “But the thing that stood out for me was how lax Alfreds joints were; he had dislocated his shoulder several times which you, Julia, have mentioned and I myself felt how lax his finger, toes, knee and arm joints were when I examined him. The joints also have collagen, specifically type II and type I collagen found in the tendons and cartilage (3) So that’s why again, I think its EDS.”
“EDS itself has multiple sub-types which can affect joints, skin, blood vessels and even the heart. However, I can only pickup that Alfred may only have the vascular and hyper-extensible type of EDS; I couldn’t find any problems with the skin”
Julia thanks Dr Alex for his informative explanation and asks how to manage Alfred’s problem. “That’s why I’d like to first do blood test on Alex to confirm this diagnosis. If the diagnosis is confirmed, we can manage him appropriately. But if it’s not, then I would have to suspect other things, even abuse unfortunately, which may involve the police. But that would be highly unlikely and unnecessary because I’m quite sure based on my previous clinical experience, I’m quite sure this is EDS” Dr Alex says confidently.
Julia thanks Dr Alex and you, then leaves to the test room for the blood tests. Dr Alex then turns around to look at you straight in the eyes and says “See that’s why, don’t be so quick to judge and conclude that a child with multiple bruises and past history of joint injury could be an abuse case. Always think of all the medical causes, in this case Ehlers-Dahnlos. So tell me, what have you learnt today?” he asks you
You explain that Ehlers Dahnlos is a disease affecting collagen. There are many types of collagen including type I found in skin and tendons, type II found in cartilage and type III found in blood vessels (3) and that the sub-types of Ehlers Dahnlos depends on which type of collagen is affected.” You then explain that Marfan Syndrome may be confused with EDS but Marfan syndrome affects fibrillin, not collagen.
“Very good” Dr Alex says. “Now go on, call in the next patient”
“Eheler Dahnlos Screening – Google Search.” Accessed February 10, 2020. https://www.google.com/search?rlz=1C1CHBF_enMY887MY887&ei=vbZAXr6ZDMHdz7sPzpSJqAw&q=eheler+dahnlo9s+screening&oq=eheler+dahnlo9s+screening&gs_l=psy-ab.3..0i13i30.2859.5962..6236…0.1..0.192.1249.13j2……0….1..gws-wiz…….0i71j0i7i30j0i13.pEuJJn32iHM&ved=0ahUKEwj-64Gj78XnAhXB7nMBHU5KAsUQ4dUDCAs&uact=5.
“Ehlers-Danlos Syndrome: Background, Pathophysiology, Etiology,” November 21, 2019. https://emedicine.medscape.com/article/1114004-overview.
Lodish, Harvey, Arnold Berk, S. Lawrence Zipursky, Paul Matsudaira, David Baltimore, and James Darnell. “Collagen: The Fibrous Proteins of the Matrix.” Molecular Cell Biology. 4th Edition, 2000. https://www.ncbi.nlm.nih.gov/books/NBK21582/.
“Marfan Syndrome (MFS): Practice Essentials, Pathophysiology and Etiology, Epidemiology,” January 27, 2020. https://emedicine.medscape.com/article/1258926-overview.