In a 78‑year‑old woman on chronic prednisone who has elevated ristocetin‑induced platelet agglutination, increased von Willebrand factor antigen with normal multimers, normal prothrombin time and activated partial thromboplastin time, normal factor VIII activity, fibrinogen 415 mg/dL, and presents with epistaxis, easy bruising, and idiopathic peripheral edema with normal BNP, creatinine, and liver function tests, is the prednisone the cause of the edema and the mild bruising/epistaxis?

Interpretation of Laboratory Findings and Clinical Presentation

The prednisone is the most likely cause of both the edema and the mild bleeding manifestations (epistaxis and easy bruising) in this patient. The laboratory findings do not indicate von Willebrand disease or a clinically significant bleeding disorder, but rather reflect physiological elevations of von Willebrand factor that are commonly seen with chronic corticosteroid use and inflammatory states.

Laboratory Interpretation: No Evidence of von Willebrand Disease

The patient's coagulation profile argues strongly against von Willebrand disease (VWD):

• Elevated ristocetin-induced platelet agglutination with elevated VWF antigen and normal multimer distribution does not fit any classic VWD pattern 1.
• Normal PT, PTT, and factor VIII (113% is normal) effectively exclude Types 1, 2A, 2M, and 3 VWD, which would show reduced factor VIII or abnormal screening tests 1.
• Normal multimer distribution excludes Type 2A VWD (which shows selective loss of high-molecular-weight multimers) and Type 2B VWD (which also shows loss of large multimers) 1.
• The elevated VWF antigen with normal multimers suggests a physiological acute-phase response rather than a pathological bleeding disorder 1.

Consideration of Rare VWD Variants

While rare variants exist with increased ristocetin sensitivity and normal multimers (Type I New York variant), these typically present with reduced VWF levels, not elevated levels as in this patient 2, 3. Additionally:

• Type 2B VWD and platelet-type VWD both show increased ristocetin sensitivity but absent large multimers, which this patient does not have 4, 5, 6.
• The patient's normal factor VIII and normal multimers with elevated VWF antigen are inconsistent with any recognized VWD subtype requiring treatment 1.

Prednisone as the Cause of Clinical Manifestations

Edema from Chronic Prednisone Use

Chronic corticosteroid therapy is a well-established cause of peripheral edema through multiple mechanisms:

• Sodium and water retention due to mineralocorticoid effects, even with glucocorticoid-predominant agents like prednisone 7.
• The FDA labeling explicitly recommends dietary salt restriction in patients on prednisone to mitigate fluid retention 7.
• With normal BNP (excluding heart failure), normal creatinine (excluding renal failure), and normal liver function tests (excluding hepatic causes), prednisone-induced fluid retention is the most parsimonious explanation for idiopathic edema 7.

Bleeding Manifestations from Chronic Prednisone Use

Chronic corticosteroid use causes capillary fragility and impaired wound healing, leading to easy bruising and mucosal bleeding:

• Prednisone causes thinning of skin and blood vessel walls, predisposing to ecchymoses and petechiae even with minor trauma 7.
• Epistaxis and easy bruising are recognized adverse effects of long-term corticosteroid therapy, particularly in elderly patients with age-related vascular fragility 7.
• The patient's normal coagulation parameters (PT, PTT, fibrinogen, factor VIII) and platelet count exclude a true coagulopathy, pointing to structural vascular fragility as the mechanism 1.

Physiological VWF Elevation from Prednisone

The elevated VWF antigen and ristocetin cofactor activity are expected findings with chronic corticosteroid use:

• Inflammatory states and corticosteroid administration elevate VWF levels as an acute-phase reactant 1.
• Pregnancy, estrogen, and inflammatory illness all increase VWF and factor VIII, and chronic prednisone creates a similar physiological milieu 1, 8.
• The normal multimer distribution confirms this is a quantitative increase in normal VWF, not a qualitative defect 1.

Clinical Recommendations

Management of Edema

• Reduce prednisone dose to the minimum effective level or consider transitioning to alternate-day therapy if the underlying condition permits 7.
• Implement dietary sodium restriction as recommended in the FDA labeling for prednisone 7.
• If edema persists despite dose reduction and salt restriction, consider adding a potassium-sparing diuretic (e.g., spironolactone) to counteract mineralocorticoid effects.

Management of Bleeding Symptoms

• Minimize prednisone dose to reduce capillary fragility and improve vascular integrity 7.
• Avoid antiplatelet agents (aspirin, NSAIDs) and anticoagulants unless absolutely necessary.
• Consider topical measures for epistaxis (nasal saline, humidification, petroleum jelly) and evaluate for local anatomic causes (septal deviation, telangiectasias).
• No specific hemostatic therapy is indicated given normal coagulation parameters and the absence of true VWD 1.

Avoiding Common Pitfalls

• Do not diagnose VWD based solely on elevated ristocetin-induced platelet agglutination when VWF antigen is elevated and multimers are normal 1, 6.
• Do not initiate VWF replacement therapy (desmopressin or VWF concentrates) in this patient, as there is no VWF deficiency and treatment would be ineffective and potentially harmful 1.
• Recognize that chronic prednisone use can mimic bleeding disorders through vascular fragility rather than true coagulopathy 7.
• If prednisone cannot be discontinued or reduced, focus on symptomatic management rather than pursuing extensive hematologic workup for a non-existent bleeding disorder 7.