Uterine doughnut in early proliferating phase: Potential pitfall in gastrointestinal bleeding studies

Abstract

A 41-year-old woman with rectal bleeding was referred to our department for gastrointestinal (GI) bleeding study. She was in early post-menstrual period and had stable vital signs. A GI bleeding study with Tc-99m SC revealed uterine blush in the pelvis. The shape of activity and quick fading excluded a GI bleeding. To rule out an intermittent bleeding, patient underwent a second bleeding study with Tc-99m RBC. Serial images showed uterine "doughnut" in the pelvis. The activity neither changed in shape nor showed distal movement with time excluding a GI hemorrhage. Uterus in early proliferating phase could be a potential pitfall in GI bleeding studies.

The SNMMI Procedure Standard/EANM Practice Guideline for Gastrointestinal Bleeding Scintigraphy 2.0

“…Obtaining lateral images or changing the position of the penis can distinguish penile activity from rectal bleeding (35). In addition, variable uterine activity during the ovulatory cycle causes fixed increased perfusion due to endometrial proliferation (76). Finally, a uterine leiomyoma may show transient, fixed activity due to hypervascularity (77)(78)(79).…”

Evaluation of consequences of the treatment of blood with extracts of Hypericum perforatum and Mentha crispa

“…RBC labeled with technetium-99m (99mTc) have been used as radiopharmaceuticals (radiobiocomplexes) for identifying slowbleeding sources of gastrointestinal bleeding (Karacalioglu et al, 2003;ManningDimmitt et al, 2005), in determination of left ventricular function by measuring ejection fractions (Leitha et al, 2001), and in the evaluation of wall motion abnormalities (Sampson, 1999;Saha, 2004). RBC labeled with 99mTc depending on a reducing agent and stannous ion (Sn 2? )…”

Splenic infarction as a pitfall on labeled red blood cell imaging

“…False positive results because of increased Tc-99m-RBCs activity due to other causes in literature are; penile blood pool mistaken for rectal bleeding, variable uterine activity during the ovulatory cycle, uterine leiomyoma, renal activity especially from an unexpected location such as a pelvic or ectopic kidney, horseshoe kidney, or a renal transplant and pooling of urine activity. [ 3 4 5 6 7 ]…”