Left-sided appendicitis is an infrequent condition characterized by pain in the left lower quadrant caused by a very long or misplaced appendix vermiformis. This ailment is associated with situs inversus totalis or midgut malrotation. The appendix may also have other locations, such as mid-inguinal, subcecal, retrocecal, pre-ileal, post-ileal, meso-celiac, pelvic or subhepatic, but in left-sided appendicitis, it is more often located in the lower left quadrant.
Left-sided appendicitis is a difficult diagnosis to establish due to the unusual presentation and is often delayed . The disease has been described between the ages of 8 and 63 and affects men 1.5 times more often than women . The presentation consists of periumbilical discomfort  followed by acute left lower quadrant pain and rebound tenderness. Clinical judgment is challenged, as many conditions cause pain in lower abdominal areas: sigmoid diverticulitis, hernias, enteritis, Meckel’s diverticulum, intestinal obstruction or volvulus, renal colic, pelvic inflammatory diseases, testicular torsion, ovarian diseases or mesenteric ischemia or adenitis  . To make the clinical picture even more puzzling, patients with left-sided appendicitis may complain about bilateral or right-sided pain . Right-sided pain in situs inversus is induced by the fact that the nervous system structures are not correspondingly transposed . The physician should also conduct a thorough history inquiry, referring to certain diseases like Henoch-Schonlein purpura, diabetes mellitus, sickle cell anemia or epiploic appendagitis  in particular, all of these may present with abdominal pain. Scoring systems, such as the Ohmann, Eskelinen or Alvarado do exist and may be employed, but their power of predictability is less than perfect .
The first step in establishing the left-sided appendicitis diagnosis is an attentive clinical examination, but this is often not revelatory. However, if the patient has situs inversus totalis, the clinician can obtain valuable hints regarding organ location using the classical methods: inspection, palpation, percussion, and auscultation. The electrocardiogram will demonstrate the right position of the heart, as will a simple posteroanterior chest radiography. An abdominal radiography will describe a right-sided gastric bubble in situs inversus. In situs solitus with midgut malrotation patients, the physician should order a barium enema in order to establish the position of the appendage, if clinical judgment dictates .
Imaging methods play key roles in the diagnosis algorithm, and ultrasonography, despite being operator dependent, is widely used. Abundant bowel gas or a large habitus causing a poor acoustic window can make examination difficult with this method. In uncertain cases, a computer tomography offers further information, with a general accuracy of 90-98%  . Abdominal films are not usually indicated because they offer no relevant information in this instance. When the cause of the pain remains unknown, an emergency diagnostic laparoscopy may be ordered.