Hand Foot Mouth Syndrome




Patient Story



Listen




A 4-year-old boy presents to a free clinic for homeless families with a low-grade fever and lesions on his hands and feet (Figures 113-1 and 113-2). The mother notes that two other kids in the transitional living center also have a similar rash. Upon further investigation, mouth lesions are noted (Figure 113-3). The mother is reassured that this is nothing more than hand, foot, and mouth disease and will go away on its own. Treatment includes fluids and antipyretics as needed.




FIGURE 113-1


Typical flat vesicular lesions on the hand of a 4-year-old boy with hand, foot, and mouth disease. (Used with permission from Richard P. Usatine, MD.)






FIGURE 113-2


Foot of the boy in Figure 113-1. Lesions tend to be on palms and soles, fingers, and toes. (Used with permission from Richard P. Usatine, MD.)






FIGURE 113-3


Mouth lesions in same boy appear as small ulcers on the lips and oral mucosa. (Used with permission from Richard P. Usatine, MD.)






Introduction



Listen




Hand, foot, and mouth disease (HFMD) is a viral illness that may affect humans and some animals, and presents with a distinct clinical presentation. The disease occurs worldwide. In 2011 and 2012, an outbreak of a much more severe and atypical form occurred in the US.




Epidemiology



Listen






  • Epidemics tend to occur every 3 years worldwide. In temperate climates, the peak incidence is in late summer and early fall.



  • HFMD generally has a mild course, but it may be more severe in infants and young children.1,2



  • There is no racial or gender predilection. Most cases affect children younger than 10 years old.3





Etiology and Pathophysiology



Listen






  • HFMD is most commonly caused by members of the enterovirus genus, especially coxsackie viruses. Epidemic infections in the US are usually caused by coxsackievirus A16, and less commonly by other coxsackievirus A strains, coxsackievirus B, or enterovirus 71.2,3 Sporadic cases occur caused by other coxsackie viruses.



  • HFMD is caused by a number of different enteroviruses around the world with different characteristics, but until recently outbreaks of an A6 strain have not been experienced in the US. Most HFMD cases worldwide are due to coxsackievirus A16.4,5



  • Outbreaks of strains of EV71 enterovirus producing large epidemics of HFMD with significant morbidity and mortality that have occurred recently in east and southeast Asia have not been seen in the US.5



  • In the fall of 2011 and early winter of 2012, 63 cases of apparent, but more severe HFMD from four US states were reported to the CDC. PCR and gene sequencing detected an A6 strain of coxsackievirus in 74 percent of clinical specimens from 38 cases.4 Cases of this atypical, severe form of HFMD have now likely been diagnosed throughout much of North America.4,6,7



  • Coxsackievirus infections are highly contagious. Transmission occurs via aerosolized droplets of nasal and/or oral secretions via the fecal–oral route, or from contact with skin lesions. During epidemics, the virus is spread from child to child and from mother to fetus.



  • The incubation period averages 3 to 6 days. Initial viral implantation is in the GI tract mucosa, and it then spreads to lymph nodes within 24 hours. Viremia rapidly ensues, with spread to the oral mucosa and skin. Rarely, aseptic meningitis may occur. Usually by day 7, a neutralizing antibody response develops, and the virus is cleared from the body.



  • HFMD may also result in neurologic problems such as a polio-like syndrome, aseptic meningitis, encephalitis, acute cerebellar ataxia, acute transverse myelitis, Guillain-Barré syndrome, and benign intracranial hypertension. Rarely, cardiopulmonary complications such as myocarditis, interstitial pneumonitis, and pulmonary edema may occur.8,9



  • Infection in the first trimester of pregnancy may lead to spontaneous abortion or intrauterine growth retardation.





Risk Factors



Listen






  • Attendance at child care centers.



  • Contact with HFMD.



  • Large family.



  • Rural residence.





Diagnosis



Listen




Clinical Features




  • A prodrome lasting 12 to 36 hours is usually the first sign of HFMD, and it usually consists of typical general viral infection symptoms with anorexia, abdominal pain, and sore mouth. Lesions are present for 5 to 10 days, and heal spontaneously in 5 to 7 days. Fever is usually mild.



  • Atypical, severe HFMD (A6) may be associated with fever as high as 103 to 105 degrees Fahrenheit, produce much more extensive, denser rash in more locations, with greater malaise and likelihood of anorexia, dehydration, and pain.4



  • Each lesion in typical HFMD begins as a 2- to 10-mm erythematous macule, which develops a gray, oval vesicle that parallels the skin tension lines in its long axis (Figures 113-1 and 113-2). The oral lesions (Figure 113-3) begin as erythematous macules, evolve into 2- to 3-mm vesicles on an erythematous base, and then rapidly become ulcerated. The vesicles are painful and may interfere with eating. They are not generally pruritic.



  • Atypical (A6) HFMD may produce lesions that are very protean in their character and evolution. Early lesions are usually maculovesicular as with the milder A16 form, but may coalesce (Figure 113-4). Others may be vesiculobullous (Figure 113-5) and may drain, or simply papular (Figure 113-6), or maculopapular and ulcerative (Figure 113-7).4,6,7



  • Cervical or submandibular lymphadenopathy may be present.


Only gold members can continue reading. Log In or Register to continue

Stay updated, free articles. Join our Telegram channel

Dec 31, 2018 | Posted by in PEDIATRICS | Comments Off on Hand Foot Mouth Syndrome

Full access? Get Clinical Tree

Get Clinical Tree app for offline access