Protein-Z-deficiency as a rare case of unexpected perioperative bleeding in a patient with spinal cord injury

Abstract

Study design: Case report describing the management of repeated perioperative bleeding probably due to Protein-Z-deficiency in a post-traumatic paraplegic patient. Objectives: To describe the difficulty in diagnosing this rare form of hypocoagulability and the monitoring and substitution concept during three elective surgical interventions. Setting: Spinal Cord Injury Center, Bergmannstrost, Halle, Germany. Case report: A 19-year-old male suffering from a post-traumatic paraplegia sub Th8 (ASIA-A) since childhood had experienced two life-threatening intraoperative bleeding incidents before finally Protein-Z-deficiency as the underlying coagulation disorder was diagnosed. After substitution of 2000 IE PPSB (Beriplex P/N) a repeatedly postponed implantation of a sphincter-externus (Brindley-) stimulator could be performed without bleeding complications, and this was also true for two additional urological interventions 1 year later. Protein-Z levels were monitored before, during and after the operations. The preoperative application of between 1000 and 2000 IE PPSB was safe and sufficient to raise the patients' plasma Protein-Z level to almost normal and so prevent excessive intraoperative blood loss. Conclusion: In case of repeated bleeding tendency of unknown origin it is mandatory to look for rare causes of hypocoagulability such as Protein-Z-deficiency. We developed a substitution concept using a plasma concentrate with guaranteed Protein-Z amount (PPSB) allowing the safe performance of elective surgical interventions.

Plasma Protein Z Levels in Healthy and High-Risk Newborn Infants

“…In SGA newborns PZ deficiency might be explained by a reduced synthesis of this protein, as already known for other plasma proteins (11).…”

“…Protein Z (PZ) is a single chain, vitamin K-dependent glycoprotein that was purified from human plasma in 1984 (7).Analogous with the majority of the coagulation proteins, protein Z is synthesized in the liver (10)With a molecular weight of 62 000 Da (11).…”

“…The half-life time in plasma is about 2.5 days (11). There are also some indications that only a fraction of the Protein-Z pool existing in plasma; higher concentrations seem to be found in proliferating vascular endothelium (11).…”

“…Few data are currently available with regard to plasma PZ concentration in newborns. There are some reports in healthy term newborns, compared with older children and adults (11), and in newborns with early respiratory distress syndrome (RDS) (12), without definitive statements, whereas no data have been published for newborns with intrauterine growth retardation (IUGR) or newborns from mothers with preeclampsia.…”

Low plasma protein Z levels are associated with an increased risk for perioperative bleedings

“…[28][29][30] Substitution of PZ with 4F-PCCs was shown to be effective in abrogating or preventing perioperative bleeding complications in affected patients. 22 Although the risk for thromboembolic complications of four-factor prothrombin complex concentrate (4F-PCC) seems to be quite low, 31 we have also to consider a growing body of evidence that low PZ is associated with an increased thromboembolic risk. 4,20 In our study Figure 3 may serve as kind of decision making aid for the clinician.…”