Category Dermatology

Subcutaneous Mycoses

Introduction Subcutaneous mycoses are a group of fungal diseases produced by a heterogeneous group of fungi that infect the skin, subcutaneous tissue, and in some cases the underlying tissues and organs. The causative agents are commonly found in the soil,…

Superficial Mycoses and Dermatophytes

Introduction Fungal disease involving human keratinized tissue may be caused by dermatophytes, non-dermatophytic fungi, or a combination of both. Superficial disease caused by non-dermatophytes is limited to the stratum corneum, hair, or both. When fungi grow on the host, there…

Human T-lymphotropic Virus 1

Key Points HTLV-1. Tropical spastic paraparesia. Infective dermatitis. Crusted scabies. Adult T-cell leukemia lymphoma. Introduction The human T-lymphotropic virus 1 (HTLV-1) was the first retrovirus identified, even before the human immunodeficiency virus (initially called HTLV-3). It is a delta retrovirus…

Measles

Key Points Measles is a highly contagious mucocutaneous disease caused by the measles virus. It is one of the most important infectious diseases of humans, responsible for millions of deaths prior to the development of measles vaccines. It manifests as…

Poxviruses

Introduction Since the last natural smallpox infection, reported in Somalia in 1977, human poxvirus infections (other than molluscum contagiosum) have only been observed sporadically either after vaccination with poxvirus officinalis (vaccinia virus), or due to zoonotic poxviruses, such as monkeypox,…

Hemorrhagic Fever and Arboviruses

Key Points Arenaviruses and hantaviruses are systemic viral diseases that are closely related to hemorrhagic fevers. Both groups of viral hemorrhagic fevers are shed in the infected rodent's saliva, urine, and feces. Ebola infection is the most aggressive viral hemorrhagic…

HIV and HIV-associated Disorders

Introduction The pandemic of human immunodeficiency / acquired immunodeficiency syndrome (HIV / AIDS) is proving to be a modern scourge. The sheer magnitude of the problem can be understood, to some extent, by looking at the figures in Tables 11-1 and 11-2 . There…

Trematodes

Key Points Infection takes place by skin contact with Schistosoma cercariae-infested water. Three clinical stages with distinctive skin manifestations are successively related to the different stages of infection: First stage (cercarial dermatitis): pruritic maculopapular rash at the site of penetration…

Cestodes

Key Points Tapeworms cause disease in humans in either of the two stages of their life cycle: the adult stage, which takes place in the intestines, where it causes mild or non-existent clinical manifestations, and the larval stage, which causes…