NOMA
Noma (necrotizing ulcerative stomatitis, stomatitis gangrenosa, or cancrum oris), first described in 1848 by Tourdes, is a devastating gangrenous condition that destroys soft and hard tissue of the face that predominantly affects young children between the ages of 1 and 4 years. “Noma” originates from the Greek word nome, which means to graze or to devour, which reflects the rapid progression of this condition. As public health initiatives improved sanitation in developed countries, the global epidemiology of noma likewise improved. Noma has become a rare occurrence in developed countries and is predominantly encountered now only in parts of Africa, Latin America, and Asia, although intermittent epidemics of noma have been reported. In response to reports from humanitarian organizations, the WHO declared noma a health priority in 1994. The WHO estimates the worldwide incidence of noma to be 500,000 cases per year, with a 79 percent mortality rate. Unfortunately, the data on the incidence of noma are likely an underestimation of the true incidence, as less than 10 percent of affected individuals actually seek medical care.
An increase in noma has been observed in developed countries over the last two decades, mostly in association with immunosuppressive therapy, human immunodeficiency virus/acquired immunodeficiency syndrome, and severe combined immunodeficiency.
Malnutrition and deficiencies in vitamins A, B6, C, and E; trace elements iron and zinc; and amino acids cysteine, methionine, serine, and glycine have been identified as possible contributing factors to immune dysfunction. Adrenal hyperfunction in PEM has also been implicated in depression of cell-mediated immunity and a decrease in mucosal resilience. Early malnutrition and chronic infections due to early weaning from breast milk may also represent predisposing factors.
Noma appears to be a polymicrobial infection, with Prevotella intermedia and Fusobacterium necrophorum being the two most frequently isolated organisms.108 Other frequently identified organisms are Tannerella forsynthesis, Peptostreptococcus micros, Campylobacter, streptococci, and enteric gram-negative rods. Although organisms are isolated from noma lesions, there is a low likelihood of transmissibility. There are no reports of outbreaks in families or villages after one child develops noma. Groupings of noma seem to be more associated with common risk factors rather than true transmission.
Parents often describe initial fever and apathy. Early acute noma often presents with soreness of the mouth, halitosis, tenderness of the lip or cheek, cervical lymphadenopathy, and purulent oral discharge. The intraoral lesion is a necrotizing stomatitis generally starting on the alveolar margin and extending to the mucosal surface of the cheek. This evolution is rapid, taking 24 to 48 hours.
Swelling and blue-black discoloration of the skin overlying the intraoral lesion develops and rapidly becomes necrotic with well-defined borders. As it becomes black, this necrotic zone expands and forms a classic cone shape, cone gangreneux, with internal destruction greater than external involvement . Laboratory investigation often shows severe anemia, a high white blood cell count, and hypoalbuminemia.
Acute necrotizing gingivitis, a painful inflammation and necrosis of the interdental papillae, was the precursor to noma. Progression to necrotic stomatitis and noma can occur if appropriate dental hygiene and antibiotics are not initiated. Acute necrotizing gingivitis is associated with poor oral hygiene, stress, and malnutrition. However, any oral mucosal ulceration or trauma, including tooth eruption and viral ulcers, can develop into noma.
Noma neonatorum is thought to be a related but separate entity from noma. Gangrenous lesions appear on patients' noses, eyelids, oral cavities, anal regions, and genitalia in apparent response to Pseudomonas aeruginosa isolated from skin lesions and many of their blood cultures. This condition is almost uniformly fatal. Clinical experience indicates that preterm and lowbirth-weight newborns, especially those with severe intrauterine growth retardation, are at greatest risk. The causative organism is usually Pseudomonas, but Escherichia coli, klebsiella, and staphylococci have occasionally been isolated. Because most cases of noma neonatorum are caused by Pseudomonas, it is possible that this represents a severe form of ecthyma gangrenosum. Almost all reported cases have been from India, China, Lebanon, or Israel, but there was one reported case in the United States in 2002, and the vast majority (98 percent) of affected children were impoverished, living in very poor homes with an average of seven children per family.
Healing lesions of noma are also difficult to manage because of extensive fibrous scars. These scars can lead to strictures of the mouth, severe dental malposition, defective speech, and even complete closure of the mouth from contractures. Management of acute noma is geared toward minimizing damage, but invasive intraoral procedures are contraindicated. Key goals of acute management are:
· Correction of dehydration and electrolyte imbalances.
· Treatment of predisposing disease (i.e., malaria, measles, human immunodeficiency virus, tuberculosis).
· Antibiotics: some researchers recommend broad-spectrum antibiotics, whereas others believe that metronidazole is adequate as anaerobic organisms predominate.
· Oral hygiene with chlorhexidine digluconate rinses.
· Nutritional rehabilitation: oral, enteral, or parenteral.
· Local wound care.
· Physiotherapy: to reduce strictures from fibrous scarring.
Surgical intervention should not occur until the acute phase has ended, and is aimed at restoring function and improving appearance to allow patients to reintegrate into society.
