Webster's New World Medical Dictionary

helical CAT scan
See 
spiral CAT scan.
Helicobacter heilmannii
A bacterium that
infects most cats, dogs, and pigs and causes them
stomach inflammation (gastritis). H. heilmannii is
not usually transmitted from animals to people, but
people who have been infected by H. heilmannii are
known to have developed gastric and duodenal
ulcers. Antibiotics can cure H. heilmannii infec-
tions. H. heilmannii is closely related to H. pylori.
Helicobacter pylori
A bacterium that causes
stomach inflammation (gastritis) and ulcers in the
stomach and duodenum. This bacterium is the most
common cause of ulcers worldwide. H. pylori infec-
tion may be acquired from contaminated food and
water or through person-to-person contact. It is
common in people who live in crowded conditions
with poor sanitation. This bacterium is also believed
to be associated with stomach cancer (gastric ade-
nocarcinoma) and a rare type of lymphoid tumor
called gastric MALT lymphoma. Infected persons
usually carry H. pylori indefinitely, often without
symptoms, unless treated with antibiotics to eradi-
cate the bacterium. Also known as ulcer bug.
HELLP syndrome
A combination of the break-
down of red blood cells (hemolysis; the H in the
acronym), elevated liver enzymes (EL), and low
platelet count (LP) occurring in pregnancy. HELLP
syndrome has been considered to be a complication
of preeclampsia and eclampsia (toxemia) of preg-
nancy, but the syndrome can also occur on its own.
Common symptoms include headache, nausea
and/or vomiting, and pain in the upper abdomen.
Increased fluid in the tissues (edema) is also com-
mon. Protein is often found in the urine. Blood pres-
sure may be elevated. Occasionally, coma can result
from seriously low blood sugar (hypoglycemia).
Treatment depends upon the stage of pregnancy, the
severity of the condition, and the overall health sta-
tus of the patient and may include corticosteroid
medications, blood transfusions, antihypertensive
medications, and antiseizure medications. Urgent
delivery is required if the health of the fetus is com-
promised or if the mother’s health is at serious risk.
HELLP syndrome can be complicated by liver rup-
ture, anemia, bleeding, and death. HELLP syndrome
can also develop during the early period after
delivery of a baby. Women with a history of HELLP