I received several, very helpful comments from Dr. Eugene Lim:1) Uric acid saturation point is 6.8 mg% at core body temperature, so 8 mg% is definitely high. When measured during an acute gout attack, sUA can be normal or even low, due to the uricosuric effect of stress cortisol produced. The sUA is therefore best assessed in-between attacks (inter-critical).
2) Gout is mostly genetic (urate exporter carriers gene defect eg ABCG2 in Asians), so a young man having gout is not surprising, especially if there’s a family history, or if he fits a metabolic syndrome profile (women are "semi-protected" till menopause as estrogen is uricosuric too).
3) The standard of care is treat-to-target: sUA at least below 6 mg%, or below 5 mg% if still having flares. Duration: at least till the dissolution of all (imaging) visible tophi. Most may need lifelong treatment to prevent flares and to normalise reno-cardiovascular (metabolic) risks.
4) (I asked about possible need for debridement…he responded) Definitely. If his sUA is maintained below 5 mg% for 2-3 years, the tophi will all melt away (unless dystrophic calcification sets in). That mass may start softening and look visibly smaller in a few months even. Surgery is not necessary unless the tophi are threatening critical structures, or if he can’t fit into his shoes.
2 radiologists suggested that PVNS (Giant Cell Tumor of the Tendon Sheath) may be considered as a possible differential diagnosis.
I shared this concern with the referring podiatrist….though I still favor Gout….as it has essentially not been treated for a decade, and the patient
has high serum uric acid.
What do You think? Can this be GCTTS….yes/no/why?
I have communicated at length with the referrer and have asked for follow up….if / when that might be.
Thanks to Drew Erie for reminding me to send this follow up…and to everyone who has shared their thoughts.
Hilary
I spoke with the podiatrist who has recently seen the patient in consultation.He says the patient is completely healthy
He’s told that the primary care physician has been treating him for Gout for 10 years with "Allopurinol when needed for acute attacks"
Currently his serum uric acid is 8, which is normal range.
I think the XR and MRI features support a diagnosis of Gout gone wildly out of control (my colleague says "it looks like gout from the Middle Ages)
I’ve not seen anything quite like this…because patients get treated
My concern is:
1. Why should an 18 yo have developed gout in the first place?
2. Is there something I’m not thinking of that can look like this other than gout?
3. FYI we don’t have or do DECT….I know some of you might suggest it, but I cannot do that in my practice
