Rhinoviruses are the most frequent cause of the common cold. One hundred two serotypes have been identified by neutralization with specific antisera, and additional strains have been isolated but are not yet typed. Rhinoviruses can be transmitted by two mechanisms: aerosols and direct contact (eg, with contaminated hands or inanimate objects).
Author: Brian Holtry
Enteroviruses
Enteroviruses are one of three types of picornaviruses that cause disease in humans. As the name indicates, picornaviruses are small (pico) ribonucleic acid (RNA) viruses that have a naked capsid structure. The family includes > 230 members divided into five genera but only three—enteroviruses, rhinoviruses, and hepatoviruses (hepatitis A virus)—cause human disease.
Enteroviruses: Clinical Syndromes
Polio vaccines and global eradication efforts have eliminated poliomyelitis from the Western Hemisphere and are expected to eliminate “wild” polio infections from the world in the near future. However, vaccine-associated cases of polio do occur. Paralytic poliomyelitis is characterized by an asymmetric flaccid paralysis with no sensory loss.
Uses and Administration of Itraconazole 100 mg (Sporanox)
Itraconazole can be used to treat various superficial fungal infections, including the dermatophytoses, pityriasis versicolor, and mucosal and cutaneous forms of candidosis. It is also effective in patients with subcutaneous infections, such as chromoblastomycosis, sporotrichosis and certain forms of phaeohyphomycosis.
Drug Interactions of Fluconazole 50, 100, 150, 200 mg Tablets (Diflucan)
Unlike itraconazole and ketoconazole, absorption of fluconazole is not reduced if it is given together with drugs that reduce gastric acid secretion. Concomitant administration of fluconazole and rifampicin has resulted in a modest reduction in blood levels of the antifungal agent. The effect is less marked than with itraconazole or ketoconazole and is due to induction of P-450 cytochrome oxidases by rifampicin with resulting enhanced hepatic metabolism of the azole drug. Like rifampicin, phenytoin undergoes cytochrome P-450-mediated hepatic metabolism and its concomitant administration with fluconazole may reduce its clearance.
Management of Tinea Unguium
Fungal infection of the nails (onychomycosis) may be caused by a number of dermatophytes as well as by a number of other moulds and Candida species. There is wide geographical and racial variation in the causative agents, but in the UK 85-90% of nail infections are due to dermatophytes and about 5% are due to non-dermatophyte moulds.
Management of Tinea Manuum
The anthropophilic dermatophytes E. floccosum, T. mentagrophytes var. interdigitate and T. rubrutn are the most common causes of tinea manuum. Less commonly, the condition is caused by zoophilic dermatophytes, such as M. canis and T. verrucosum, or geophilic dermatophytes, such as M. gypseum. Hand infection may be acquired as a result of contact with another person, with an animal, or with soil, either through direct contact, or via a contaminated object such as a towel or gardening tool. Autoinoculation from another site of infection can also occur.
Management of Tinea Pedis
The term tinea pedis is used to refer to dermatophyte infections of the feet. These infections often involve the interdigital spaces, but chronic diffuse desquamation can affect the entire sole. The anthropophilic dermatophytes E. floccosum, T. mentagrophytes var. interdigitale and T. rubrutn are the commonest causes of tinea pedis in the UK and North America.
Management of Tinea Cruris
The dermatophytes most often encountered in tinea cruris are E. floccosum and T. rubrum. Maceration and occlusion of the skin in the groin give rise to warm moist conditions that favour the development of the infection. Tinea cruris is a common form of dermatophytosis.
Management of Tinea Corporis
Tinea corporis is caused by E. floccosum and many species of Trichophyton and Microsporum. Infection with anthropophilic species, such as E. floccosum or T. rubrum often follows autoinoculation from another infected body site, such as the feet. Tinea corporis caused by T. tonsurans is sometimes seen in children with tinea capitis and their close contacts. Tinea corporis commonly occurs following contact with infected household pets or farm animals, but occasional cases result from contact with wild mammals or contaminated soil.