Cardiovascular (I00-I99).
- Ruptured aortic aneurysm (outpouching of the aorta that has ruptured) – usually left-sided rupture with continuous pain (annihilation pain) and tendency to collapse; possible additional symptoms: diffuse abdominal and back pain, a poorly palpable inguinal pulse of variable intensity, and dizziness (older patients)
Liver, gallbladder, and bile ducts-pancreas (pancreas) (K70-K77; K80-K87).
- Cholelithiasis (gallstones; sex ratio: males to females is 1: 2-3).
- Cholecystitis (gallbladder inflammation).
- Pancreatitis (inflammation of the pancreas, acute.
Mouth, esophagus (esophagus), stomach and intestines (K00-K67; K90-K93).
- Appendicitis (inflammation of the appendix; age 10-30 years).
- Diverticular disease/diverticulitis – disease of the colon in which inflammation forms in outpouchings of the mucosa.
- Ileus (intestinal obstruction)
- Irritable bowel syndrome (colon irritable)
Musculoskeletal system and connective tissue (M00-M99)
- Facet syndrome (synonym: facet joint syndrome) – pseudoradicular pain symptomatology (pain in which the nerve itself is not affected in its function), usually caused by chronic irritation of the so-called facet joints (zygapophyseal joints; intervertebral joints: small, paired joints that exist between the articular processes (processus articularis) of adjacent vertebrae and ensure the mobility of the spine).
- Musculoskeletal pain from the level Th 10-12.
Neoplasms – tumor diseases (C00-D48)
- Urinary bladder carcinoma (cancer of the urinary bladder; urinary obstruction).
- Testicular carcinoma (testicular cancer; retroperitoneal metastasis).
- Hypernephroma (renal cell carcinoma).
- Pheochromocytoma – neuroendocrine (affecting the nervous system) catecholamine-producing tumor of the chromaffin cells of the adrenal medulla (85% of cases) or sympathetic ganglia (nerve cord that runs along the spine in the thoracic (chest) and abdominal (stomach) regions) (15% of cases)
- Prostate carcinoma (prostate cancer; lymph nodes obstructing the ureters).
Pregnancy, childbirth, and puerperium (O00-O99).
- Extrauterine pregnancy – implantation of the fertilized egg outside the uterus (womb) such as: Tubalgravidity (tubal pregnancy), Ovariangravidity (pregnancy in the ovary), Peritonealgravidity/Abdominalgravidity (abdominal pregnancy), or Cervicalgravidity (a pregnancy in the cervix).
- Pregnancy – acute flank pain develops in approximately 3% of all pregnant women; upper urinary tract infections (pyelonephritis) are the most common.
Psyche – nervous system (F00-F99; G00-G99).
- Neuralgia (nerve pain), acute segmental.
Genitourinary system (kidneys, urinary tract – reproductive organs) (N00-N99).
- Dysmenorrhea (menstrual pain).
- Glomerulonephritis – kidney disease associated with inflammation of the renal corpuscles (glomerulum, plural glomeruli or glomerula, corpuscula renales) in the kidney
- Urinary tract infection (UTI)
- Hydronephrosis – dilation of the renal cavity system, which in the medium and long term is associated with destruction of kidney tissue.
- Nephrolithiasis (kidney stones)
- Ovarian cyst (ovarian cyst), pedunculated.
- Ovulation pain (pain caused by ovulation).
- Pyelonephritis (inflammation of the renal pelvis; upper urinary tract infection).
- Urolithiasis (urinary stones; 30-60 years).
- Cystic kidney disease
All diagnoses that can explain abdominal pain are also among the important differential diagnoses of flank pain.