A two-year-old male presented with a chief concern of recent changes to his toenails. His parents noted ridging, lifting and occasional shedding of the toenails. The shedding was painless but the parents expressed concern regarding the cause of these symptoms as well as the cosmetic impact. The child did not have a remarkable medical history but his parents noted that he had a case of hand, foot and mouth disease (Coxsackie virus) about a month prior. During this illness, he experienced painful sores in the oral cavity and a rash to the hands. The acute illness did not involve the feet. The parents provided a picture of the hand rash (see left photo above), which appeared maculopapular in nature with areas of crusting on the palmar surface only.
A colleague also shared a case of a second patient with a similar history. This 18-month-old patient had no significant medical history, but exhibited similar nail changes to both the toenails and fingernails after a recent diagnosis of hand, foot and mouth disease.
Key Questions To Consider
1. Are the nail changes consistent with hand, foot and mouth disease?
2. What are other differentials should one consider?
3. How does one treat nails like the ones in the aforementioned pediatric patients?
4. What is the prognosis?
Answering The Key Diagnostic Questions
1. Yes, onychomadesis may occur as a result of hand, foot and mouth disease, and may present after the onset of the acute illness.
2. Erythema multiforme as the rash may present similarly.
3. One should perform conservative care with the reassurance that nail changes are temporary and normal nails will likely return.
4. The prognosis is excellent in most cases as it is a self-limiting disease. There are cases, however, with severe consequences and timely diagnosis is imperative. If you suspect hand, foot and mouth disease, and the family is unaware of the diagnosis, it may be worthwhile to refer to the patient’s pediatrician.
What You Need To Know About Hand, Foot and Mouth Disease
Richardson and Leibovitz first described hand, foot, and mouth disease in 1958 when an outbreak of vesicles appeared on the mouth, hands and feet of children in a suburb of Toronto in 1957.1 A few years later, similar outbreaks occurred in California and England, all due to Coxsackie virus A16 (CA16).1
Hand, foot and mouth disease is a common viral infection, which is usually acute in nature and highly contagious. While most cases present in pediatric patients under the age of 10, adults can also contract the disease. The disease is more common in males and it is transmitted through direct contact.2 Painful mouth lesions usually occur first, causing refusal of food. Other signs of illness include low grade fever, malaise and, in some cases, a maculopapular rash and/or vesicular lesions on the hands and feet. Skin lesions will occur concurrently or shortly after the oral lesions. There are cases, however, only involving one area. The lesions frequently occur on the interdigital skin but also on the ventral creases of the digits, medial and lateral borders of the feet and less frequently on the sole of the foot.1
Lesions can vary in number from one to 100 and red papules two to 10 mm in diameter develop first. In the center of many of these lesions is a gray vesicle, which is slightly raised and appears flaccid.3 The vesicles run along the skin lines and may be crescentic on digital tufts. They appear within the first few days of the illness but may continue to erupt over weeks. Lesions eventually desiccate and scale off within a week, or may ulcerate, which delays healing time. The lesions may be slightly pruritic. If there is any pain associated with the lesions, it is not a predominant feature.
One may attempt to isolate virus from these lesions and this would most likely reveal the viral strain. However, the clinical picture is so distinct that virologic confirmation is usually unnecessary.
The maculopapular rash is characteristically non-specific in appearance. When this occurs on the buttocks, it can resemble a diaper rash. However, the rash may also appear on the face, arms or legs, and is similar in appearance to erythema multiforme.
Coxsackie A16 is not the only viral type associated with this disease. In other sporadic cases, patients are infected with Coxsackie A5 (CA5), Coxsackie A10 (CA10), human enterovirus 71 and Coxsackie A6 (CA6) in adults.2-4 Cases are more prevalent during the spring and summer months. Hand, foot and mouth disease is reportedly the most common infectious disease in China, ranging from 500,000 to 1,000,000 cases per year.2
The disease is self-limiting within seven to 10 days. Accordingly, treatments are only geared to address the symptoms. However, there are existing reports of later onset onychomadesis, meningitis, Guillain-Barre syndrome, meningoencephalitis, paralytic polio, myoclonus and somnolence mostly in a subgenotype of the enterovirus 71 strain (C4aEV71) affecting children under the age of five. These children specifically had low levels of vitamin A, which was associated with reduced immunity and therefore a higher susceptibility to more severe cases of the disease.
What About The Nails? Notes On Pathogenesis And Treatment
Nail changes associated with this disease can include superficial peeling of a pale nail plate with eventual nail shedding or bulging from the proximal to distal edge, and then breaking off completely from the proximal border.5 It is important for the podiatrist to recognize these changes and ask if there was prior hand, foot and mouth disease infection to prevent unnecessary treatment. Changes in the nails can occur as early as six days after the resolution of vesicles and up to four to six weeks after the onset of the disease.
Nail pathology associated with hand, foot and mouth disease usually presents without pain or inflammation, and its mechanism is unknown. Studies suggest that periungual inflammation from the viral infection may be the cause or that the nail matrix is directly damaged by viral replication, based on the presence of Coxsackie A6 in shed nails.6 The nail changes begin as greenish-yellow patches proximally and spread toward the free edge. The nails then shed distally concomitantly with the new normal nail until complete separation of the nail plate occurs. Onychomadesis is also self-limiting. One may or may not note Beau’s lines and the toenails and/or the fingernails may be involved.
Understanding How Hand, Foot And Mouth Disease Can Affect Adults
Recent reports show an increased number of adult-onset hand, foot and mouth disease. Mostly, this involves the family of the infected, the pediatrician, immunocompetent adults in contact with the infected child and the immunocompromised.2,3 Adult patients may have an altered disease course and clinical manifestations. Unlike the pediatric patient in whom mucosal lesions are an almost universal finding, adult patients may not have these lesions, or they do not persist. Palmoplantar pruritic and petechial eruptions in adults may be due to the greater thickness of the epidermis in this age group versus pediatric patients. The disease duration can last up to two years, especially in cases of immunosuppression.4
In 2014, a 23-year-old male in Barcelona presented to a local hospital with lesions to his hands, feet and mouth, mild fever and general malaise.2 According to a case report, he had no remarkable medical or surgical history. Admittedly, he had been in contact with a two-year-old female who was diagnosed with hand, foot and mouth disease seven to 10 days beforehand and other members in the child’s family had similar symptoms.2 Providers recommended analgesics, diet and hygiene to prevent aggravation of his symptoms and within a week, the disease subsided with no recurrence at follow-up in 15 days.2
Another case report published in 2019 discussed a 52-year-old male patient who presented with a three-day history of high-grade fever, malaise and gingival pain followed by an asymptomatic widespread rash, which included his upper back, chest, buttocks, hands and feet.4 The blood workup was non-contributory but Coxsackie antibodies were positive. Within two weeks, the condition improved spontaneously and no complications emerged over the follow-up period.4
Hand, foot and mouth disease is a virus that can affect patients of any age, and can have varied presentations. It is important to recognize the signs and symptoms associated with this highly contagious virus. Timely diagnosis allows for better control of disease transmission and avoidance of unnecessary treatment.
Dr. DeLauro is currently on the Board of Directors of the American Board of Podiatric Medicine, and is a contributing author to Fitzpatrick’s Dermatology in General Medicine. She is in private practice in New Jersey and New York, and is affiliated with the Hoboken University Medical Center in Hoboken, N.J.
1. Richardson HB Jr, Leibovitz A. Hand, Foot, and Mouth Disease in children; an epidemic associated with Coxsackie virus A-16. J Pediatrics. 1965;67:6-12.
2. Omaña-Cepeda C, Martínez-Valverde A, del Mar Sabater- Recolons M, Jané-Salas E, Marí- Roig A, López-López J. A literature review and case report of hand, foot and mouth disease in an immunocompetent adult. BMC Res Notes. 2016;9(1):165.
3. Higgins PG, Warin RP. Hand, foot, and mouth disease. A clinically recognizable virus infection seen mainly in children. Clin Pediatrics (Phila). 1967;6(6):373-376.
4. Farah M, El Chaer F, El Khoury J, El Zakhem A. Erythema multiforme-like hand, foot, and mouth disease in an immunocompetent adult: a case report. Int J Dermatology. 2020;59(4):487- 4889.
5. Long D, Zhu S, Li C, Chen C, Du W, Wang X. Late-onset nail changes associated with Hand, Foot, and Mouth Disease: a clinical analysis of 56 cases. Ped Derm. 2016;3(4):424–428.
6. Mortada I, Mortada R, Al Bazzal M. Onychomadesis in a 9-month-old boy with hand-foot-mouth disease. Int J Emerg Med. 2017;10(1):26.
7. Chiu H-H, Liu M-T, Chung W-H, et al. The mechanism of onychomadesis (nail shedding) and Beau’s lines following hand-foot-mouth disease. Viruses. 2019;11(6):522.
8. Starace M, Alessandrini A, Piraccini BM. Nail disorders in children. Skin Appendage Disord. 2018;4(4):217-229.