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the registration system and the active vaccination since 1962 have continuously declined the incidence of tuberculosis ( tb ) in korea . despite of these efforts
, the incidence of tb in korea is high among the organization for economic cooperation and development countries . in 2009 , in korea , the reported tb cases per 100,000 were 74.3 , and the actual incidence is presumed as 90 cases per 100,000 . according to data from the registration center ,
the proportion of extra pulmonary tb shows increased tendency since 2003 . of extra pulmonary cases ,
the reported incidence of primary tb in performed appendectomies varies from 0.1 to 3.0% , and it is 1.5 to 30% of all patients who were diagnosed with tb . herein , we report the case of a child with primary tuberculous appendicitis accompanied with mesenteric mass .
a 14 year - old boy complained of intermittent right lower quadrant abdominal pain for one day .
he had no medical history and received all vaccinations , including bcg ( bacille de calmette - guerin ) vaccine , as scheduled .
one month prior to admission , he started a baseball camp training in his school .
he did not experience febrile sensation , weight loss or cough . on physical examination ,
laboratory findings showed that the white blood cell count and the c - reactive protein were within normal range .
abdominal computed tomography revealed diffuse enlargement of the entire appendix ( about 12 mm ) , with cystic change at the tip of the appendix ( fig .
1 ) . also , the abnormal calcified mass was detected on abdominal computed tomography .
the 3.3  27 cm mass was located at the right side of the right iliac artery , inferior to the second portion of the duodenum and anterior to the right psoas muscle ( fig .
it was accompanied by internal necrosis and was assumed to be the lymph - node from the mesentery .
we decided to perform laparoscopic appendectomy and excision of the mesenteric mass . under general anesthesia ,
we used three trocars , as follows : a 12-mm trocar at the infra umbilical portion , a 5-mm trocar at the left lower abdominal quadrant , and a 5-mm trocar at the suprapubic portion .
we found no ascites . the appendix was diffusely enlarged and distended , and it showed suppurative change ( fig .
the intra - abdominal mass was protruded from the mesentery , was adjacent to the second portion of the duodenum and showed as a yellowish , calcified mass .
it was dissected from the mesentery by hook and harmonic scalpel . after specimen retrieval , the necrotic material from the mesenteric lymph - node showed cheese - like changes .
we obtained the acid - fast bacteria ( afb ) stain and culture from the specimen .
the afb stain and culture revealed growth of the mycobacterium tuberculosis complex . from the histologic diagnosis ,
both the appendix and the mesenteric lymph - node showed chronic granulomatous inflammation , with caseous necrosis ( fig .
tb can affect all organ systems , and the most commonly affected region is the lung . of extra - pulmonary locations of tb , bones and the urinary system
are the most frequently affected ( 30% and 24% , respectively ) , followed by lymph nodes ( 13% ) .
abdominal tb may involve the gastrointestinal tract , peritoneum , lymph nodes , or solid organ ; however , peritoneum and abdominal lymph nodes are the most common sites . in the pediatric literature ,
abdominal tb has been described infrequently , in 2 of 1,000 and 5 of 1,700 patients in industrialized countries .
, 0.6% by singh et al . , 2.3% by gupta   in india and 0.13% by sohn et al .   in korea . in japan , until 2010
, primary tb of the appendix was observed in only 11 out of 29 cases of all tb of appendix .
the cause of this rarity may be explained by the fact that the intestinal contents do not make direct contact with the luminal mucosa of appendix . as early as 1914 ,
william j mayo said that the appendix is an interesting organ because , although it has abundant lymphoid tissue as adenoid or peyer 's patch , was little involved in tb .
it has been suggested that the appendix was primarily infected either hematogenously , from a distant focus which was not clinically detectable , or by direct contact with contaminated sputum or food .
also , the appendix was secondarily infected from : 1 ) direct invasion of adjacent organs , such as the ileocecal region or the urinary system , 2 ) retrograde lymphatic spread from distant lesions in either the ileum or the ascending colon , and 3 ) via appendicular serositis or periappendicitis , in peritoneal tb .
this makes pre - operative diagnosis difficult and delayed , resulting in a high percentage of complicated appendicitis .
borow and friedman suggested three clinical features : 1 ) the chronic form - mild to moderate right quadrant abdominal pain , with nausea and vomiting , 2 ) the acute form - sudden onset of right quadrant abdominal pain , 3 ) the latent form .
it showed typical granuloma , with caseous necrosis surrounding the epithelioid cells and the langhans giant cells . in this case , the appendix and the mesenteric mass also showed the tb infection .
we considered that the mesenteric lymphnode involvement did not require further evaluation of intestinal tb , and we administered anti - tb medication .
the regimen for anti - tb medication was the standard four drug chemotherapy , including isoniazid , rifampin , pyrazinamide and ethambutol .
the anti - tb medication after appendectomy is known to decrease the incidence of the usual complications , such as stump blowout or fecal fistula . in conclusion
the involvement of the mesenteric lymph node presenting with abdominal mass was possible with primary tuberculous appendicitis .
tuberculosis primarily affecting the appendix is extremely rare and the diagnosis is difficult . here 
 , we report the case of a 14-year - old healthy boy presenting with right lower quadrant abdominal pain . on computed tomography , the distended appendix with 3.3  2.7 cm mass located at the right side of the right iliac artery was detected . 
 there was neither bowel wall thickening nor active lung lesion . 
 after laparoscopic appendectomy with mass excision , histopathological examination revealed chronic granulomatous inflammation , with caseous necrosis of the appendix . 
 we made a diagnosis of primary tuberculosis of appendix and administrated anti - tuberculosis medication .