Ref: Nelson's Textbook of Pediatrics, 19th edition. Robbins Pathologic Basis of Disease, 8th edition & Bailey and Love's Short Practice of Surgery 25th Edition Explanation: localized abdominal tenderness is the single most i: hie finding in the diagnosis of acute appendicitis. In Children, if the diagnosis is delayed beyond 36-48 hr, the perforation rate exceeds 65%. Perforation is most common in young children, with rates as high as 82% for children <5 yr and approaching 100% in infants. Nausea and vomiting occur in more than half the patients and usually follow the onset of abdominal pain by several hours. " (Ref: Nelson) Acute appendicitis The IC surgical procedure performed on an emergency basis is an appendectomy. Most common in the first 2 decades Pathophysiology Appendiceal obstruction is the most common initiating event of appendicitis. Hyperplasia of the submucosal lymphoid follicles of the appendix accounts for approximately 60% of obstructions (most common in teens), In older adults and children the fecalith is the most common etiology (35% ). Obstruction of the appendiceal lumen is followed by increased intraluminal pressure secondary to continued mucosal secretion and bacterial overgrowth. The appendiceal wall becomes thinned and lymphatic and venous obstruction occurs. Necrosis and perforation develop when the arterial flow is compromised. Diagnosis. The diagnosis of acute appendicitis is made by clinical evaluation. Although laboratory tests and imaging procedures can be helpful, they are of secondary importance. Clinical presentation Symptoms Progressive, persistent midabdominal discomfort caused by obstruction and distention of the appendix, which stimulates the visceral afferent autonomic nerves (T8-10 distribution). Anorexia (90%) and a low-grade fever (<38.5degC). Nausea and vomiting (70%) and 10% have diarrhea. Once the inflammation extends transmurally to the parietal peritoneum, the somatic pain fibers are stimulated, and the pain localizes to the RLQ. Peritoneal irritation is associated with pain on movement, mild fever, and tachycardia. One-fourth of patients present initially with localized pain and no prior visceral symptoms. The onset of symptoms to the time of presentation is usually less than 24 hours for acute appendicitis and averages several hours. In Children, if the diagnosis is delayed beyond 36-48 hr. the perforation rate exceeds 65%. Perforation is most common in young children, with rates as high as 82% for children <5 vr and approaching 100% in infants. Nausea and vomiting occur in more than half the patients and usually follow the onset of abdominal pain by several hours. Physical examination McBurney's point tenderness two-thirds of the distance from the umbilicus to the anterosuperior iliac spine). Localized abdominal tenderness is the single most reliable finding in the diagnosis of acute appendicitis. The presence of pain in the RLQ during gentle finger percussion in the LL.Q (Rovsing's sign) indicates peritoneal irritation. The degree of direct tenderness is appreciated. The degree of muscular resistance to palpation parallels the severity of the inflammatory process. Cutaneous hyperesthesia is often present overlying the region of maximal tenderness. Exacerbation of pain with passive stretching of the iliopsoas muscle (positive psoas sign) implies the presence of local inflammation in the area of the muscle (e.g.. retrocecal appendicitis). A pelvic appendix may produce hypogastric pain with passive internal rotation, a positive Obturator sign. A palpable mass in the RLQ suggests a peri-appendiceal abscess or phlegmon. Laboratory evaluation. Complete blood cell count, serum electrolytes, and urinalysis should be obtained preoperatively for patients with suspected appendicitis. A serum pregnancy test also must be performed for all ovulating women. Complete blood cell count A leukocyte count of greater than 10,000 cells/ mL with polymorphonuclear cell predominance (>75%) is common in the child and young adult with appendicitis. The total number of WBCs and the proportion of immature forms increase if there is an appendiceal perforation. Urinalysis It is abnormal in 25-40% of patients with appendicitis. Pyuria, albuminuria, and hematuria are common. Radiologic evaluation USG is most useful Findings associated with acute appendicitis include The appendiceal diameter of greater than 6 mm. Lack of luminal compressibility Presence of an appendicolith. Abdominal CT scan is generally performed only in complex cases or in patients with atypical presentations. Barium enema (BE* Diagnostic laparoscopy Differential diagnosis Gastrointestinal diseases Gastroenteritis Mesenteric lymphadenitis Meckel's diverticulitis Perforated peptic ulcer disease Diverticulitis Cholecystitis Typhlitis Urologic diseases Pyelonephritis Ureteral colic Gynecologic diseases PID Ectopic pregnancy Ovarian cysts Ovarian torsion. Treatment Preoperative preparation Intravenous isotonic fluid replacement Nasogastric suction in patients with peritonitis. Preoperative antibiotic coverage Antibiotic therapy Broad-spectrum antibiotic coverage is initiated preoperatively Appendectomy The treatment of appendicitis is an appendectomy. Drainage of appendiceal abscess Management remains controversial. Systemic antibiotics and considered for Percutaneous US- or CT-guided catheter drainage Elective appendectomy 6-12 weeks later The appendix must be removed because the patient has a 60% risk of developing appendicitis again within 2 years. Complications Perforation It is accompanied by severe pain and fever. It is unusual within the first 12 hours of appendicitis but It is present in 50% cases < 10 years and > 50 years. Fever, tachycardia, generalized peritonitis, and abscess formation. Treatment is an appendectomy, peritoneal irrigation, and broad-spectrum intravenous antibiotics for several days. Postoperative wound infection The risk is decreased by IV antibiotics administered before skin incision. The incidence increases from nonperforated appendicitis (3%) to a perforated or gangrenous appendix (4.7%). Wound infections are managed by opening, draining, and packing the wound to allow healing by secondary intention. Intravenous antibiotics are indicated for associated cellulitis or systemic sepsis. Intraabdominal and pelvic abscesses Occur most frequently with perforation of the appendix. Best treated hv percutaneous CT- or US-guided aspiration. If the abscess is inaccessible or resistant to percutaneous drainage, operative drainage is indicated. .Antibiotic therapy can mask but does not treat # >i prevent a significant abscess. Pylephlebitis It is septic portal vein thrombosis, usually is caused by Escherichia cob Presents with high fevers, jaundice, and eventually hepatic abscesses. CT scan demonstrates thrombus and gas in the portal vein. Prompt treatment (operative or percutaneous) of the primary infection followed by IV antibiotics. Enterocutaneous fistulas from a: Leak at the appendiceal stump closure May require surgical closure but most close spontaneously.