Necrotizing enterocolitis (NEC) is an inflammatory condition of the gastrointestinal tract primarily affecting preterm infants, characterized by high mortality and morbidity rates in the neonatal intensive care unit (NICU). Diagnosis and treatment remain challenging, with feeding practices, gut colonization, and ischemic injury being significant contributing factors to the disease's pathophysiology. Management options include medical therapy, surgical interventions, and supportive care, with outcomes varying based on the extent of intestinal involvement and the timing of treatment.

2. INTRODUCTION
• Is an acquired inflammatory condition of the
GI tract with variable degree of tissue necrosis
• Occur in 3/ 1000 births
• Disease first described in 1960
• Still difficulty in diagnosis and treatment
approach

3. • Leading cause of mortality and morbidity in NICU
• Most common newborn surgical emergency
• Incidence is 5-10% among newborn infants in NICU
• The incidence widely vary among different
geographic areas
• About 90% of cases occur in preterm
• 7-13 % cases may occur in term

4. Risk factor
• Prematurity is the greatest risk factor
• The lowest the birth weight the highest
incidence of NEC
• Indomethacin
• Umblical artery cathetherization
• Maternal cocaine use
• If it occurs in term neonate usually occurs with
Down syndrome, HSD, CHD, asphyxia

5. prematurity
• the mean gestational age of NEC was 31
weeks and average birth weight, 1460 g)
• Greatest risk before 28week and below 1kg
• Age of onset is within 1st
and 2nd
week usually
• inverse relationship between the age at onset
of NEC and gestational age
• Declining risk after 35-36week

6. Physiology of premature gut
• Decrease peristalsis leading to less clearance
of bacteria and stasis
• Fewer B lymphocytes so less IgA
• Invasion of mucosa by bacteria
• Less pepsin, gastric acid, mucous resulting in
increased bacterial proliferation

7. Role of feeding
• Composition and quantity of feeding
• Highly concentrated formulas,,,, increased PAF
• High osmolarity…. Damage to villi
• Fatty acids ….mucosal injury
• Large carbohdrate…. Hydrogen production
• No clear guideline
• 90% occur after feeding
• Minimal volume feeding 20ml/kg before going to
full feeding for about 10days found to decrease NEC

8. pathophysiology
• Maladaptive response of the gut to feeding
and bacterial colonization
hypoxic ischemic insult; due to diminished
splanchnic perfusion
Enteral feeding
Bacterial overgrowth
Exaggerated inflammatory response

9. Ischemia….
• Ischemia and reperfusion injury
• Cellular hypoxia leading to increase xanthine
oxidase production
• XO result in increased production of xanthine and
uric acid during reperfusion
• Release of reactive oxygen species
• Damage of cell membrane
• Membrane permeability and bacterial
translocation will be the effect

10. Exaggerated inflammatory response
• Key mediators of inflammation being NO, PAF,
TNFa
• Maladaptive vasoregulatory reponses
• leading to vasoconstriction
• Increased level of inflammaory mediators

11. enteral feeding
• Breast-fed infants colonized predominantly
with gram positive bacteria
• In contrast, formula-fed infants colonized
predominantly by coliforms, enterococci, and
Bacteroides species
• Affected symbiotic gut microbial axis

12. Role of infectious agent
• Affection of symbiotic gut-microbe relationship
• gut colonization during the newborn period
• In 2/3rd of cases bacteria isolated
• E. coli, Klebsiella, Enterobacter, Pseudomonas,
Clostridium, and coagulase-negative
Staphylococci
• Pneumatosis intestinalis:the accumulation of
hydrogen gas in the intestinal wall due to
fermentation of carbohydrates by intestinal flora

13. The agreed hypothesis
• the interaction among the enterocyte,immune
effector cells, and resident microbiota initiates
an inflammatory cascade that becomes
unbalanced

15. pathology
• Involves single( 50% ) or multiple segment of
inestine
• About 20 % of surgically treated NEC have feature
of pan necrosis
• bowel is markedly distended with patchy areas of
thinning
• serosal surfaces are typically red to gray
• and may be covered by a fibrinous exudate
• Frank gangrene, hemorrhagic fluid

16. Histopathologic changes
• Acute on chronic inflammation
• coagulation necrosis of the superficial mucosa
• Edema and hemorrhage of the submucosa
• In resolving cases epithelial regeneration and
fibrosis
• Small vessels thrombosis
• Full and partial thickness necrosis
• Perforation
• Pneumatosis intestinalis

17. diagnosis
• Physiologic instability
that may mimic sepsis
• Hypo/hyperthermia
• Bradycardia
• Apnea
• shock
• Feeding intolerance
• Gi bleeding(79-86%)
• Gastric residuals
• Abdominal distension(70-
98%
• Diarrhea(26%
• Vomiting(70%
• Progressing sepsis
• Fixed abdominal mass
• Abdominal wall erythema

18. Physical examination
• Abdominal distension
• Fixed palpable mass
• Palpable bowel loops
• Edema/erythema abdominal wall

19. laboratory
• neutropenia, thrombocytopenia, and metabolic
acidosis
• Paracentesis: When there is high suspcion with
no radiologic evidence of perforation
• Positive paracentesis: aspiration of more than 0.5
mL of brown fluid that contains bacteria on Gram
stain
• Is done for extensive pneumatosis intestinalis
and failed medical therapy

20. diffferntial
• Ileus with sepsi
• Focal intestinal perforation

21. imaging
• Multiple gas filled loops of intestine
• Pneumatosis intestinalisc: pathognomonic for
NEC
• a collection of cystic or linear lucencies in the
bowel wall,
• Frequency may reach 19-98%but may be
absent in upto 14% of cases of NEC

25. • Portal venous gas: linear branching radiolucencies
overlying the liver and often extending to its
periphery
• incidence of 10% to 30%.poor prognosis
• Pneumoperitoneum: in 12-30% of patients
• Best seen on lateral decubitus film
• Football sign, double wall sign,
• Only 63% of patients with perforation show the
xray sign

26. • Intraperitoneal fluid: gasless abdomen, flank
opacity, separation of bowel loops
• Persistent dilated bowel loop: dilated bowel
loop remained unchanged for 24 to 36 hours

30. managment
• Nonoperative management
• aggressive fluid resuscitation,
• bowel rest : stop feeding, NG tube decompression
• broad-spectrum antibiotics,
• and close monitoring for the earliest signs of
perforation
• Frequent PE, abdominal xray every 6-24 hour based on
the stage
• Correct metabolic acidosis and electrolyte abnormality

31. • Indication for surgery
• Pneumoperitoneum
• Relative indication
• Positive paracentesis:
• Failure of medical management
• Single fixed bowel loop on xray
• Adominal wall erythema
• Palpable mass
• Severe neutropenia, severe thrombocytopenia, acidosis

32. Operative management
• Up to 30-50% may develop advanced NEC requiring
operation
• Maximal optimization before operation
• Appropriate time after gangrene has occurred but
before perforation
• Both smal bowel and colon 45%
• Ileocecal region being the most common
• Small bowel20%
• Colon30%

33. laparatomy
• May be focal, multifocal, paninvolvement
• Focal disease : resection and stoma
• Multifocal disease: resection and multiple
anastomosis
• Clip and drop back technique

35. • Depend on the condition of the patient and
the extent of the bowel involved
• Resect gangreneous part so as to reduce
sepsis
• Early intervention to reduce conatamination
• Prevent short bowel syndrome

36. paracentesis

37. • Peritoneal drainage vs exploraory laparatomy
• Primary peritoneal drainage
• In ELBW/VLBW infant as a treatement
• In other neonates as away of stabilizing before the
definitive laparatomy
• From studies from those PD done 40% doesn’t
require additional laparatomy and other 40%
laparatomy was needed
• Recent studies no difference in outcome

38. • Peritoneal drainage
• making a right lower
quadrant incision,
• irrigating the peritoneal
cavity,
• placing a small rubber
drain in the abdomen

39. • enterostomy versus primary anastomosis
• The traditional trend was resection and stoma
• In a localized ,focal disease with a good bowel
condition and stable neonate primary
anastomosis could be considered
• For multifocal and pan NEC proximal diverting
jejunostomy

40. • Clip and drop technique
• Gangreneous bowel resected out and the end
tied of and left in the abdomen
• 24-48hour relaparatomy for possible stoma or
anastomosis

41. • Prognosis
• Medical management fails in approximately
20-40% of patients with
• pneumatosis intestinalis at diagnosis; of these,
10-30% die

42. Postop complication
• Wound infection
• Stoma complication
• Sepsis
• Neuro developemtal problems
• Intestinal stricture
• Short bowel syndrome

43. • Prevention
• Breast feeding
• Following feeding guidelines
• Trophic feedings are advised
• ?prophylactic antibiotic