Medical Mystery of the Week
Because of the COVID19 pandemic, you are practicing telemedicine. You are shown a
picture of a 35-year old man's leg (see below). He states the lesions are extremely
painful and began after blunt trauma to the shin. He has had intermittent diarrhea,
abdominal cramping, and an occassional bloody stool for the past six months.
What is your diagnosis, what test(s) do you recommend to confirm your suspicions,
and what treatment, if any, do you recommend?
DIAGNOSIS: Pyoderma grangrenosum (PG) (bulous variety) in a patient with inflammatory
bowel disease (ulcerative colitis).
In the last decade there has been considerable advance in our classification of PG-associated
autoinflammatory syndromes. Acronyms for these syndromes include PAPA (pyogenic arthritis,
PG and acne congoblata), PASH (PG, acne and suppurative hydradenitis), PAPASH (PG,
suppurative hydradenitis and psoriatic arthritis), PASS (PG, acne congoblata, suppurative
hydadenitis and axial spondyloarthritis), PAC (PG, acne, and ulcerative colitis),
and PsAPSC (psoriatic arthritis, PG, suppurative hydadenitis and Crohn's disease).
In addition to their clinical presentations, these syndromes can be distinguished
by the presence or absence of several genes including those that encode proline-serine-threonine
phosphatase-interacting protein 1 (PSTPIP1), nicastrin (NCSTN), Mediterranean fever
(MEFV) and nucleotide-binding oligomerization domain-containing protein (NOD) [1].
There are several clinical presentations of PG - bullous, characterized by painful
gun-metal colored bullae; pustular; and painful nodular lesions similar to those seen
in Sweet's syndrome. All of these forms of PG are associated with elevations in peripheral
blood neutrophil levels.
1. Saternus, R.; Schwingel, J.; Muller, C.S.L.; Vogt, T.; Reichrath, J. Ancient friends,
revisited: systematic review and case report of pyoderma gangrenosum-associated autoinflammatory
syndromes. J. Translational Autoimmunity. 2020, https://doi.org/10.1016/j.jauto.2020.100071.