Epilepsy is a disorder of recurrent unprovoked (or reflex) seizures; the key to diagnosing epilepsy is estimating the risk of recurrence. Epilepsy may be diagnosed if a patient has two or more seizures at least 24 hours apart, a first-time seizure with factors that increase the risk of recurrence, or an epilepsy syndrome. When determining the type of epilepsy, first identify the seizure type(s), then the corresponding epilepsy type. Consider if the epilepsy is potentially syndromic or nonsyndromic. Consider the underlying etiology (structural, genetic, infectious, immune, or metabolic). Focal epilepsies may be classified based on their region of onset, that is, frontal, temporal (mesial/lateral), parietal, occipital, or insular. Ictal and interictal EEG findings vary with the type of focal epilepsy.

A wide variety of insults including infectious agents, medications and endogenous and environmental chemical substances may cause injury to the gastric mucosa. This may take the form of inflammation (gastritis), reactive changes without inflammation (termed gastropathy by some authors), or a combination of the two. The histological appearances may be a ‘pattern’ of injury that is non-specific and can be seen in association with several aetiologies, or there may be histological features that are highly characteristic of a single injurious agent. In this chapter, ‘gastritis’ is considered in three sections – patterns of injury (with many potential causes), specific types of gastritis, and gastric mucosal injury related to medical therapies. A practical approach to diagnosis including potential diagnostic pitfalls is emphasised, as is the need for accurate endoscopic and clinical information when interpreting these specimens. Common entities, such as Helicobacter pylori gastritis and reactive gastritis, as well as rare conditions and other infections are considered. The discussion focuses on endoscopic biopsies (the most common specimen seen in practice) but these changes may be present in the resected stomach in the setting of both benign and malignant disease and also, increasingly, in specimens removed at the time of bariatric surgery.

The Guts of the Matter is a study of our oldest ecological problem: the transmission of infectious intestinal pathogens from human waste. Over deep time, fecal pathogens have killed innumerable infants and young children and been a principal constraint on human population growth. Over the past several generations, we have gained increasing control over the transmission of infectious intestinal disease. These advances have contributed to an ongoing population explosion that is dramatically transforming global ecological systems. The introduction provides a guide to the book’s structure, introducing the individual chapters with a brief summary of each.