acute appendicitis , one of the commonest surgical emergencies , affects nearly 7% of the world 's population and accounts for about 1% of all surgical operations . faecoliths formed by mineral deposits layered with faecal debris and lodged in the appendix are called appendicoliths . the prevalence of faecoliths in the general population is 3% , and appendicoliths are seen in 10% cases of acute appendicitis . a 25-year - old male presented to us with pain in the right flank for 1 day . urinalysis was normal , and abdominal ultrasound raised a suspicion of small calculi in the right kidney . non - contrast computed tomography ( ncct ) abdomen revealed a few subcentimetric calculi in both kidneys without hydronephrosis or hydroureter . [ figure 1c and d ] ( mineral core ) , composed mainly of calcium and struvite on spectral analysis [ figure 1a and b ] . he underwent laparoscopic appendectomy using a 10-mm supra - umbilical camera port and two 5 mm ports at the supra - pubic region and the left iliac fossa , respectively . a pre - ileal appendix was found hidden in flimsy adhesions posterior to the terminal ileum . an incidental meckel 's diverticulum was also found [ figure 1f ] , which was not pathological and was left alone . the mesoappendix was cut using harmonic scalpel ( johnson and johnson make ) and the appendix was cut at the base between ligatures [ figure 1e ] . it was removed using a glove bag after enlarging the supra - umbilical incision because of the large stone size  2.5 cm  3.0 cm [ figure 1 g and h ] . ncct abdomen ( a and b ) the ct spectral analysis of the appendicolith shows the highest peak of the histogram corresponding to struvite - calcium ( c ) multiplanar reconstruction ( mpr ) coronal image showing appendicolith 2.50 cm size ( longitudinal ) ( d ) axial image showing appendicolith 2.10 cm size ( transverse ) ( e - h ) laparoscopic appendectomy , procedure , specimen and appendicolith ( e ) multiple ligations of base of appendix ( f ) meckel 's diverticulum ( g ) size of appendicolith 3 cm on longest axis ( h ) size of appendicolith 2.5 cm on the perpendicular axis acute appendicitis was first reported by fitz in 1886 , and wangensteen and bowers proposed the theory of an obstructive component as a causative factor in 1937 . other proposed aetiologies include lymphoid hyperplasia , constipation , trauma , diet , genetic predilection , hypersensitivity and mucosal ulceration . appendicolith on plain abdominal x - ray is a reliable sign of appendicitis ( 70% ) . however , computed tomography ( ct ) is more sensitive , detecting even non - calcified faecoliths . on ct , appendicoliths appear as laminated bodies with gas in centre or homogenous opacity . when symptomatic , they carry 90% probability of acute appendicitis and 50% higher risk of perforation and abscess formation . some authors have found good correlation ( 65 - 100% ) between faecoliths on ct and appendicitis , while others have not . in a retrospective review by lowe et al . , an appendicolith detected on ct had a sensitivity of 65% , specificity of 86% , and positive predictive value of 74% for the diagnosis of appendicitis . despite appendicoliths being common , a giant appendicolith ( > 2 cm ) is extremely rare and only sporadically reported . others include a 2.1 cm appendicolith reported by garg and a 2.2 cm stone by kaluarachchi . our case is probably the largest documented stone ( 3  2.5 cm ) and the first whose chemical composition has been determined preoperatively by spectral analysis . the authors have not received any resources from a third party , directly or indirectly , to complete this work . the authors have not received any resources from a third party , directly or indirectly , to complete this work .
acute appendicitis is one of the commonest surgical emergencies worldwide . 
 there is considerable variation in prevalence of appendicoliths with appendicitis . 
 most of the patients with appendicoliths are asymptomatic and they are not pathognomic for acute appendicitis . 
 however , appendicoliths show increased association with perforation and abscess formation . 
 appendicolith are quite common , being present in 3% of general population and in nearly 10% cases of appendicitis . however , giant appendicoliths measuring over 2 centimeters ( cms ) are extremely rare . computed tomography ( ct ) 
 has increased their pre - operative diagnosis considerably . 
 use of spectral analysis can give us the details of composition of the stone pre - operatively . 
 we present a young male diagnosed pre - operatively on non - contrast computed tomography ( ncct ) to have a giant calcium struvite appendicolith . 
 on laparoscopy he had a 3 cm stone and an incidental meckel 's diverticulum and underwent appendectomy . 
 the case is presented for the unique size of the appendicolith alongwith review of literature .