-penia- (s), -penias (pl), -penic, pen-, penia- +

(Greek > Modern Latin: abnormal reduction, decrease in, insufficient, deficiency. Originally, the meaning was poverty, need; sometimes it is erroneously or incorrectly rendered as -poenia)

kaliopenia
A deficiency or insufficiency of potassium in the body.
leukocytopenia, leukopenia, leukopenic, leucopenic
1. An abnormal lowering of the white blood cell count.
2. An excessive reduction in the number of white blood cells.
3. The antithesis of leukocytosis; any situation in which the total number of leukocytes in circulating blood that is less than normal.
lipopenia
An abnormally small amount, or a deficiency, of lipids (fats and waxes) in the body.
lymphopenia, lymphopenic, lymphocytopenia
A reduction, relative or absolute, in the number of lymphocytes in circulating blood.
monocytopenia, monopenia
Diminution in the number of monocytes in circulating blood.
neutropenia, neutropenic, neutrophilopenia
The presence of abnormally small numbers of neutrophils (mature white blood cells) in the circulating blood of the body.

Neutrophils are white blood cells (WBCs) produced in the bone marrow that ingest bacteria. Neutropenia is sometimes called agranulocytosis or granulocytopenia because neutrophils make up about 60% of white blood cells and have granules inside their cell walls.

Neutropenia is a serious disorder because it makes the body vulnerable to bacterial and fungal infections.

The normal level of neutrophils in human blood varies slightly according to age and race. Infants have lower counts than older children and adults, and African Americans tend to have lower counts than Caucasians or Asians.

osteopenia
1. Decreased calcification or density of bone; a descriptive term applicable to all skeletal systems in which such a condition is noted; it carries no implication about causality.
2. Reduced bone mass due to inadequate osteoid synthesis.
pancytopenia
1. The pronounced reduction in the number of erythrocytes, all types of white blood cells, and the blood platelets in the circulating blood.
2. A condition in which the blood shows a relative deficiency of all three cellular components (erythrocytes, leucocytes, and platelets).
panleukopenia
A highly contagious and fatal disease of cats, particularly young cats, caused by feline panleukopenia virus, a member of the family Parvoviridae, and manifested by severe leukopenia, prostration, fever, vomiting and diarrhea.
penalgesia (s) (noun) (no pl)
The reduction in the number of pain and touch spots in trigeminal neuralgia: In medical school, Nancy learned about penalgesia referring to the decrease of the amount of pain and contact locations in the fifth cranial nerve.
peniagenous
Induced or caused by poverty.
peniaphobia (s) (noun) (no plural)
A morbid hatred of being in a state of poverty: Sam worked a lot at different jobs because he always wanted to have enough money for fine furniture and other items in his home, and never to be destitute, and his friends thought he suffered from peniaphobia!
phosphopenia, phosphorpenia
Low serum phosphate levels in the blood.

Phosphates are important in the maintenance of the acid-base balance of the blood, the principal ones being monosodium and disodium phosphate.

prothrombinopenia
Abnormally small amounts of prothrombin in circulating blood; hypoprothrombinemia.
reticulocytopenia, reticulopenia
Paucity of reticulocytes in the blood. The reticulocytes are young red blood cells that become more numerous during the process of active blood regeneration.