Sherris Medical Microbiology, Sixth Edition

Book Preface

With this 6th edition, Sherris Medical Microbiology enters its fourth decade. We are pleased to welcome new authors, Michael Lagunoff (virology) and Paul Pottinger (antibiotics, parasitology) from the University of Washington; L. Barth Reller (laboratory diagnosis, bacteriology) from Duke University; and Charles R. Sterling (parasitol-ogy) from the University of Arizona. Jim Plorde, an author since the first edition, is enjoying a well-deserved rest. John Sherris, the founding editor, continues to act as an inspiration to all of us.

BOOK STRUCTURE

The goal of Sherris Medical Microbiology remains unchanged from that of the first edition (1984). This book is intended to be the primary text for students of medicine and medical science who are encountering microbiology and infectious diseases for the first time. Part I opens with a chapter that explains the nature of infection and the infectious agents at the level of a general reader. The following four chapters give more detail on the immunologic, diagnostic, and epidemiologic nature of infection with minimal detail about the agents themselves. Parts II-V form the core of the text with chapters on the major viral, bacte-rial, fungal, and parasitic diseases, and each begins with its own chapters on basic biology, pathogenesis, and antimicrobial agents.

CHAPTER STRUCTURE

In the specific organism/disease chapters, the same presentation sequence is maintained throughout the book. First, features of the Organism (structure, metabolism, genetics, etc) are described; then aspects of the Disease (epidemiology, pathogenesis, immunity) the organism causes are explained; the sequence concludes with the Clinical Aspects (mani-festations, diagnosis, treatment, prevention) of the disease. The opening of each section is marked with an icon and a snapshot of the disease(s) called the Clinical Capsule, which is placed at the juncture of the Organism and Disease sections. A clinical Case Study fol-lowed by questions in USMLE format concludes each of these chapters. In Sherris Medical Microbiology, the emphasis is on the text narrative, which is designed to be read compre-hensively, not as a reference work. Considerable effort has been made to supplement this text with other learning aids such as the above-mentioned cases and questions as well as tables, photographs, and illustrations. The Glossary gives brief definitions of medical and microbiologic terms which appear throughout the book.

STUDY AIDS

The marginal notes, a popular feature since the first edition, are nuggets of information designed as an aid for the student during review. If a marginal note is unfamiliar, the relevant text is in the paragraph immediately adjacent. The supplementary materials at the end of the book now include two new additions. The first is Infectious Diseases: Syndromes and Etiologies, a set of tables which re-sort the material in the rest of the book in a clinical context. Here you will find the common infectious etiologies of the major presentations of infectious diseases whether they are viral, bacterial, fungal, or parasitic. It is hoped these will be of value when the student prepares for case discussions or sees patients. A set of 100 Practice Questions is also included. These are in USMLE format and in addition to the ones following the case studies at the end of the organism-oriented chapters in Parts II-V.

For any book, lecture, case study, or other materials aimed at students, dealing with the onslaught of new information is a major challenge. In this edition, much new material has been included, but to keep the student from being overwhelmed, older or less important information has been deleted to keep the size of this book no larger than of the 5th edi-tion. As a rule of thumb, material on classic microbial structures, toxins, and the like in the Organism section has been trimmed unless its role is clearly explained in the Disease section. At the same time, we have tried not to eliminate detail to the point of becoming synoptic and uninteresting. Genetics is one of the greatest challenges in this regard. With-out doubt this is where major progress is being made in understanding infectious diseases, but an intelligent discussion may require using the names and abbreviations of genes, their products, and multiple regulators to tell the complete story. Whenever possible we have tried to tell the story without all the code language. The exciting insights offered by genom-ics must be tempered by the knowledge that they begin with inferences based on the identi-fication of sequences characteristic for a particular gene. The gene product itself may or may not have been discovered. Here, we have tried to fully describe some of the major genetic mechanisms and refer to them later when the same mechanism reappears with other organ-isms. For example, Neisseria gonorrhoeae is used as an example of genetic mechanisms for antigenic variation in the general chapter on bacterial pathogenesis (Chapter 22), but how it may influence its disease, gonorrhea, is taken up with its genus Neisseria (Chapter 30).

A saving grace is that our topic is important, dynamic, and fascinating—not just to us but to the public at large. Newspaper headlines now carry not only the name but also the anti-genic formulas of E coli and Influenza virus along with their emerging threats. Resistance to antimicrobial agents is a regular topic on the evening news. It is not all bad news. We sense a new optimism that deeper scientific understanding of worldwide scourges like HIV/AIDS, tuberculosis, and malaria will lead to their control. We are confident that the basis for understanding these changes is laid out in the pages of this book.