Hand, foot and mouth disease in an immunocompromised adult treated with aciclovir

Molecular epidemiology of hand, foot, and mouth disease in Karnataka, India in 2022

BACKGROUND

Hand, foot, and mouth disease (HFMD) is an enteroviral disease that occurs as outbreaks and sporadic cases in India. In this study, we investigated and characterized the aetiology of HFMD cases that occurred in Karnataka, South India from April to October 2022.

METHODS

Throat swabs, vesicular swabs, urine, and blood samples from suspected cases were analysed by reverse transcription polymerase chain reaction (RT-PCR) for the detection of enteroviruses. Molecular typing of the enterovirus-positive samples was carried out by amplifying the partial virion protein 1(VP1) gene sequence, followed by sequencing and phylogenetic analysis.

RESULTS

Out of the 187 samples received from 82 cases, 93 (50%) tested positive (55/82 cases, 67%) for enteroviruses, with the majority of the HFMD cases reported in paediatric population of less than 5 years (36/55, 65.4%), while 3 cases (3/55, 5.4%) were adults. Out of the 55 enterovirus-positive cases, 31 showed partial VP1 region amplification and 19 of these cases were typed as coxsackievirus A16 (CV-A16) (13/19, 68.4%) and CV-A6 (6/19, 31.6%). The CV-A16 strains identified belonged to subclade B1c while two CV-A6 strains belonged to subclade E2. On molecular testing for other viruses causing fever-rash symptoms, 4/27 (15%) enterovirus-negative cases were detected as herpes simplex virus (1 case) and varicella zoster virus (3 cases) positive.

CONCLUSION

The main causative agent of HFMD in Karnataka in 2022 was CV-A16, followed by CV-A6. Apart from the common paediatric HFMD cases, adult cases were also reported during this period. Further studies involving laboratory and clinical investigations are essential for monitoring and managing HFMD in the community.

Recent advances in anti-coxsackievirus A16 viral drug research

Hand, foot and mouth disease, a childhood disorder caused by enteroviruses, is intermittently endemic in the Asia-Pacific region and endangers the lives of many infants and young children. Coxsackievirus A16 (CV-A16) is one of the major pathogens causing hand, foot, and mouth disease on occasion, resulting in catastrophic neurological sequelae and patient death. Currently, no clinical interventions are available that completely block the CV-A16 infection. Therefore, research on anti-CV-A16 treatment continues to be a significant focus of interest. This report provides a detailed background on and an introduction to CV-A16; a description of the viral gene and protein structures and a summary of the current advances in pharmaceutical targets, drug research and other related areas.

A case report of severe systemic infection with neurological HFMD symptoms followed by an accidental puncture of thumb during HFMD sample collection

A 34-year-old female clinical virology assistant was punctured with a contaminated lancet used for sampling from a suspected Hand, Foot, and Mouth disease (HFMD) patient. Five days after a puncture, the disease symptoms manifested, including high fever, ague, and stiff neck. Skin rashes suddenly appeared after day 6. Stiff neck and fever were relieved two days after the rash appeared, and rashes disappeared gradually by the next five days. Samples for molecular detection and virus cultivation were taken from the patient. Real-time PCR found the enteroviral RNA in the throat swab and skin rashes. The specific CPE of Enteroviruses appeared on the Vero cell line after three days of incubation. In this case transmission occurs through needle injury and results in the systemic disease, so unusual and unexpected viral transmission should be considered when dealing with samples.

[Atypical hand, foot and mouth disease in adults: A note on 6 cases]

INTRODUCTION

Hand, foot and mouth disease (HFMD) is form of viral dermatosis well known among the pediatric population, in whom it has a typical presentation. However, it is less common in adults, with a more heterogeneous presentation, potentially making diagnosis extremely challenging for the clinician.

PATIENTS AND METHODS

This was a retrospective case series from 2013 to 2018 of HFMD in adults, with all cases being confirmed by cutaneous polymerase chain reaction (PCR). We studied the clinical, epidemiological and viral characteristics of each patient.

RESULTS

This series of 6 cases comprised 4 men and 2 women, with a mean age of 42.5 years. Five patients presented extended purpuric lesions, four had bullous lesions, and three showed cutaneous signs without any mucosal lesions. Extended lesions on the trunk were found in four patients. One patient presented rosette-shaped pustular lesions on the limbs, one had eczema-like lesions on the scalp, and one presented extended purpuric lesions on the soles.

DISCUSSION

These different cases of adult HFMD raise questions about differential diagnosis in relation to other acute cutaneous and mucous diseases. It is essential to be aware of these different types of presentation of the disease in order to determine the diagnosis and discuss preventive measures.

Enteroviruses and Parechoviruses

Infections with enteroviruses and human parechoviruses are highly prevalent, particularly in neonates, where they may cause substantial morbidity and mortality. Individuals with B-cell-related immunodeficiencies are at risk for severe enteroviral infections, usually a chronic and fatal meningoencephalitis. In transplant recipients and patients with malignancy, enterovirus infections typically involve the respiratory tract, but cases of severe, disseminated infection have been described. The mainstay of diagnosis for enterovirus and human parechovirus infections involves the use of molecular diagnostic techniques. However, routine nucleic acid-detection methods for enteroviruses will not detect human parechoviruses. Laboratory diagnosis of these viral infections is important in determining a patient's prognosis and guiding clinical management.

Update on hand-foot-and-mouth disease

Hand-foot-and-mouth disease is a viral exanthem caused, primarily by Coxsackie A16 and enterovirus 71 with typical clinical features of fever, painful papules and blisters over the extremities and genitalia and an enanthem involving ulceration of the mouth, palate, and pharynx. Other enteroviruses have recently been noted to cause severe neurologic illness and paralysis (enterovirus 68) with variable cutaneous features. A recent outbreak of Coxsackie A6 infection has been seen worldwide with cases reported in the United States, Japan, Southeast Asia, and Europe. These cases have caused extensive cutaneous disease variants, some of which are not previously recognized in Coxsackie infection, namely vesicobullous and erosive eruptions, extensive cutaneous involvement, periorificial lesions, localization in areas of atopic dermatitis or in children with atopic dermatitis (the so-called eczema coxsackium), Gianotti-Crosti-like lesions, petechial/purpuric eruptions, delayed onychomadesis, and palmoplantar desquamation. Finally, adult cases appear to occur with this form of hand-foot-and-mouth disease, likely due to fecal-oral transmission in a household setting.

A Case of Hand-foot-mouth Disease in an Immunocompetent Adult

Hand-foot-mouth (HFM) disease is primarily a disease of children, although it can be seen in immunocompromised adults. We describe a case of HFM disease in a 35-year-old immunocompetent male. He presented with multiple, 1~2 mm sized, erythematous vesicular papules on both hands and feet. Histopathological findings of a skin biopsy showed superficial perivascular lymphocytic infiltration, focal keratinocyte necrosis, and reticular degeneration. Because delayed diagnosis can cause spread of the disease to children, dermatologists should be aware that HFM disease can occur in adults with intact immune systems.

[Viral exanthem]

The most frequent cause of exanthematous diseases are viral infections, which provoke skin alterations either directly or via the reaction of the immune system. In many distinct parainfectious clinical pictures, several viruses from quite different groups are able to produce a specific exanthem. Dominant pathogens for exanthematous diseases include non-polio enteroviruses, respiratory viruses, Epstein-Barr virus, HHV-6 and HHV-7 viruses as well as parvovirus B19. In many cases exanthemata present with maculate or maculopapular features in disseminated distribution. Some exanthematous diseases exhibit typical predilection sites. In addition to the clinical picture, diagnosis is based on the patient's history, observation of the patient's general condition, awareness of the season in the year, and physical examination. In uncertain cases and for scientific studies, blood analysis, smear tests, and histological investigation confirm the diagnosis. Knowledge of exanthematous disease, which usually run harmless course, is essential for differentiation of life-threatening disorders. This article presents exanthematous viral diseases depending on age at primary manifestation.