Omphalitis – Causes, Presentation and Treatment

Omphalitis is an infection of the umbilicus and/or surrounding tissues, occurring primarily in the neonatal period. It is a true medical emergency that can rapidly progress to systemic infection and death.

The estimated mortality is between 7% and 15%.

Early recognition and treatment are essential to prevent the morbidity and mortality associated with omphalitis.

Omphalitis typically presents as superficial cellulitis that can spread to involve the entire abdominal wall and may progress to necrotizing fasciitis, myonecrosis, or sepsis.

Though it is rare in the developed world, it is a common cause of neonatal mortality in less developed countries.

It occurs more commonly in hospitalized preterm infants.

It is uncommon to find this condition after the neonatal period but some instances have been reported in adults too.

There is no sex-predilection but males are associated with a worse prognosis.

Risk factors

• Low birth weight
• Prolonged rupture of membranes
• Maternal infection
• Umbilical catheterization
• Nonsterile delivery
• Prolonged labor
• Birth at home
• Poor cord care
  • Application of cow dung is also associated with higher rates of omphalitis.
• Immune system abnormalities
  • Defects in leukocyte adhesion
  • Defect in the lymphocyte function
  • Defects in interferon production
  • Neonatal alloimmune neutropenia
  • Congenital neutropenia
• Anatomic abnormality
  • Patent urachus
  • Patent omphalomesenteric duct
  • Urachal cyst may be present

Pathophysiology

Omphalitis is a polymicrobial infection. That means it is often caused by a mixture of bacteriae, both aerobic and anaerobic.

85% of infections are caused by aerobic bacteriae such as Staphylococcus aureus. Methicillin-resistant staph infections are also known.

Application of herbal and other poultices, human milk, animal dung, ash may lead to  Clostridium tetani as an infective agent.

Anaerobic bacteriae especially B fragilis is seen more in cases like prolonged rupture of membranes and amnionitis, etc.

The umbilical cord which has connective tissues and blood vessels is cut after the child is born and an umbilical stump remains which separates from umbilicus over a few days by a mechanism which is not very clear. But the following processes are thought to contribute

• Granulocyte influx and phagocytosis
• Desiccation
• Tissue infarction and necrosis
• Action of collagenase and other proteases

As the stump undergoes necrosis, it is a good medium for bacterial growth and if there is an invasion, omphalitis results.From there, the infection might move to fascial planes (necrotizing fasciitis), abdominal muscles (myonecrosis), and the umbilical vessels.

Sepsis may occur if there is a systemic spread of the infection. Septic embolization could infect other organs especially causing endocarditis and liver abscess formation. Infection of the viscera may lead to spontaneous evisceration, peritonitis, bowel obstruction, abdominal abscesses, etc.

Apart from these immediate complications, there could be cavernous transformation of the portal vein, portal vein thrombosis, extrahepatic portal hypertension, and biliary obstruction in the long term.

Portal hypertension could lead to gastroesophageal varices and cause bleeding.

Clinical Presentation

The condition is mainly seen in newborns.

Tenderness, erythema, and induration of the umbilicus and surrounding tissues suggest the involvement.

The disease might start as superficial cellulitis and can progress to involve the entire abdominal wall.

Purulent discharge or bleeding from the cord stump may occur.

A foul-smelling odour suggests anaerobic infection.

Symptoms like lethargy, poor feeding, fever, and irritability suggest sepsis. These could sometime be an initial presenting feature too.

A rapidly progressing redness or gas below the skin indicate necrotizing fasciitis.

An anatomical abnormality should be present if there is a history of urine or stool discharge from the stump.

Extensive local disease [necrotizing fasciitis or myonecrosis] is indicated by:

• Ecchymoses
• Blue discoloration
• Bullae
• Peau d’orange appearance
• Crepitus
• Petechiae
• Progression of cellulitis despite antimicrobial therapy

Systemic signs of Sepsis

Temperature dysregulation which is manifested by either fever [>38 degrees] or hypothermia [temperature <36°C].

• Tachycardia (pulse >180 beats per minute [bpm])
• hypotension

• • (systolic blood pressure <60 mm Hg in full-term infants)
  • delayed capillary refill (<2-3 seconds)

• Breathing problems

• • Apnea
  • Tachypnea (respirations >60/min)
  • Grunting
  • Flaring of the alae nasi
  • Intercostal or subcostal retractions

• Distended abdomen or absent bowel sounds
• Jaundice
• Petechiae
• Cyanosis
• Hypotonia or hypertonia

Differential Diagnoses

• Discharging patent urachus [communication between the bladder and umbilicus]
• Umbilical granulomas
• Umbilical polyps [firm masses of urachal embryologic remnants]
• Funisitis [inflammation of umbilical cord only, not vessels]

Staging of Neonatal Omphalitis

• Grade 1
  • Funisitis
  • Purulent umbilical discharge
  • Could be foul smelling
• Grade 2
  • Grade 1+ cellulitis of the abdominal wall
• Grade 3
  • Grade 2+ systemic involvement such as sepsis, DIC
• Grade 4:
  • Grade 3 + ecchymosis, crepitus, bullae, and involvement of superficial and deep fascia and associated muscle

Diagnostic Studies

• Gram stain of specimen from wound surface or muscle [in myonecrosis]
• Culture of the specimen
• CBC
  • May show neutrophilia or neutropenia
  • Immature-to-total neutrophil ratio greater than 0.2 could be an indicator of systemic bacterial infection in the first few days of life.
  • Thrombocytopenia may be present.
• C-reactive protein
• Erythrocyte sedimentation rate
• Neutrophil CD64 count

In case of sepsis and suspected DIC [disseminated intravascular coagulation]

• Peripheral blood smear
• Prothrombin time/Activated partial thromboplastin time
• Fibrinogen
• D-dimer
• Chest radiograph
• Urinalysis, Urine culture
• Cerebrospinal fluid [CSF culture]
• Routine biochemistry may show reduced glucose levels and calcium levels.

Blood gas analysis may show metabolic acidosis.

X-rays of the abdomen may reveal intra-abdominal wall gas.

Ultrasonography shows

• thickening of fascia and accumulation of fluid between subcutaneous fat and muscle when fascia is involved
• May detect anatomic abnormalities.

CT scan shows the extent of tissue involvement and can detect anatomical abnormalities.

Treatment of Omphalitis

All critical children may require a transfer to ICU (Intensive Care unit).

The infection is treated by antibiotics and supportive care.

Antibiotics

• Parenteral administration covering both gram positive and negative organisms till culture report is available
• Anaerobic coverage may be provided by metronidazole or clindamycin.
• In uncomplicated omphalitis
  • Parenteral antistaphylococcal+aminoglycoside
  • Intravenous clindamycin or metronidazole, if required.( In case of doubt, err on side of administration)
• Omphalitis complicated by necrotizing fasciitis or myonecrosis
  • • Requires aggressive approach
    • Antibiotics against gram-positive and negative organisms plus for anaerobes

Supportive care [as needed]

• Respiratory support
• Oxygen supplementation
  • Hypoxemia
  • Apnea unresponsive to stimulation.
• Fluid administarion or vasoactive agents, or both for hypotension.
• Transfusion [for DIC or bleeding]
  • Platelets
  • Fresh frozen plasma
  • Cryoprecipitate for disseminated intravascular coagulation (DIC) or clinical bleeding

Enteral feeding should not be given in case of systemic infections until acute infection improves.

In these infants, parenteral nutrition is required.

Role of surgery

In the case of necrotizing fasciitis and myonecrosis, early and complete surgical debridement of the affected tissue and muscle is often life-saving.

More than one surgical procedure could be required.

Monitoring

Uncomplicated omphalitis gets better [redness decreases] after 12 to 24 hours of the start of antimicrobial therapy.

If the child does not respond, look for

• Disease progression
• Anatomic defect
• Immunodeficiency state
• Wound inspection regularly, including surgical cases
• Monitor and manage metabolic problems which may occur

Prevention of Omphalitis

Dry cord care as recommended by WHO should be followed in institutional delivery or after home delivery where neonatal mortality rates are low. It involves clamping of the cord and apply nothing on the cord.

However, not all cases can be managed by dry cord care. For example, when delivery occurs in an unhygienic environment and areas where neonatal mortality is high.

Application of antimicrobial agents to the cord in these cases decrease bacterial colonization and prevents omphalitis.

Triple dye, alcohol, and Povidone-iodine are common topical agents.

Prognosis

Uncomplicated omphalitis has a favorable outcome with almost zero mortality.

Overall omphalitis has 7-15% mortality but this rises to as high as 90% in necrotizing fasciitis or myonecrosis.

Following are associated with poor prognosis

• Male sex
• Premature child
• Septic delivery

References

• Fraser N, Davies BW, Cusack J. Neonatal omphalitis: a review of its serious complications. Acta Paediatr. 2006 May. 95(5):519-22.
• Weber DM, Freeman NV, Elhag KM. Periumbilical necrotizing fasciitis in the newborn. Eur J Pediatr Surg. 2001 Apr. 11(2):86-91.
• O’Brien PH, Meredith HC, Vujic I, Schabel SI. Obstructive jaundice caused by cavernous transformation of the portal vein postneonatal omphalitis. J S C Med Assoc. 1979 May. 75(5):209-10.
• Karumbi J, Mulaku M, Aluvaala J, et al. Topical umbilical cord care for prevention of infection and neonatal mortality. Pediatr Infect Dis J. 2013 Jan. 32(1):78-83.
• Goldenberg RL, McClure EM, Saleem S. A review of studies with chlorhexidine applied directly to the umbilical cord. Am J Perinatol. 2013 Sep. 30(8):699-701.
• Gormley D. Neonatal anaerobic (clostridial) cellulitis and omphalitis. Arch Dermatol. 1977 May. 113(5):683-4.
• Karumbi J, Mulaku M, Aluvaala J, English M, Opiyo N. Topical umbilical cord care for prevention of infection and neonatal mortality. Pediatr Infect Dis J. 2013 Jan. 32 (1):78-83.
• Cosme Jimenez A, Barrio Andres J, Bujanda Fernandez de Pierola L, et al. Clinical characteristics of nonneoplastic cavernomatous transformation of the portal vein at a Gastroenterology Service in Spain. Rev Esp Enferm Dig. 2000 Jul. 92 (7):448-57. .