6th February 2024

A 43-year-old female presents to the acute medical unit with severe abdominal pain.

A 43-year-old female presents to the acute medical unit with severe abdominal pain. The pain was described as severe, constant pain in her central abdomen. She reports several episodes in the past with no apparent cause identified. The skin on her upper and lower limbs showed hyperpigmented bullous lesions in a sun-exposure distribution. CT scan in the emergency department was unremarkable. Urinary aminolevulinic acid and porphobilinogen levels were elevated. Gene mutation in the PPOX gene was demonstrated. 

Which of the following products is likely elevated in this case?