This type presents with exercise-induced muscle cramps and weakness (sometimes rhabdomyolysis), myoglobinuria, as well as with haemolytic anaemia causing dark urine a few hours later.[7] Hyperuricemia is common, due to the kidneys' inability to process uric acid following damage resulting from processing myoglobin. Nausea and vomiting following strenuous exercise is another common indicator of classic PFK deficiency. Many patients will also display high levels of bilirubin, which can lead to a jaundiced appearance.