A 33-month-old girl who presented with hematochezia and ecchymotic skin lesions was diagnosed with Mycoplasma pneumoniae pneumonia by serology and polymerase chain reaction
[ncbi.nlm.nih.gov]
Furthermore, most patients experience epistaxis, gastrointestinal hemorrhages provoking melena and/or hematochezia, and hematuria due to lesions of the urinary tract.
[symptoma.com]
[…] immunoglobulin types G, A, or M, directed against coagulation factors causes a propensity to bleed that manifests in form of spontaneous hemorrhages, e.g., epistaxis, melena and hematochezia
[symptoma.com]