Econstudentlog

Lupus – The Essential Clinician’s Guide

I read this book for different reasons than the ones that usually apply when I find myself reading medical textbooks; I’d wish those reasons did not exist.

The book is nice; there’s a lot of information in there despite the low page count, and it’s slightly less technical than are some related books (e.g. this one, which I’ve also briefly had a look at). The book has a lot of data, but as a result of the nature of the publication a lot of information related to this data is missing from the coverage; for example we’re told that “[o]ral ulcers are present in 20% of patients”, but we’re not told how many patients this estimate is based upon, and/or how confident we are that that number is correct. You have to take some stuff on faith and I’ve read the book assuming that given the background of the author, his reported estimates are at least in the right ballpark. The author might argue that providing such additional ‘meta-data’ as well to the readers could have easily doubled the page-count without adding much information which is relevant to the people reading the publication, and if he did do that I’m not actually sure I’d necessarily disagree with him; it’s a good book in terms of what it sets out to do, and I can’t really blame the author for not writing a different book. Part of why I chose to give the book a high rating is also that I liked it much better than some other superficially similar short books I’ve read, e.g. this one.

I’ve added some observations from the book below and added some hopefully helpful links which may make the post a bit easier to read.

“Based on the definitions of lupus given in Chapter 2, 50% of all cases of lupus are systemic lupus erythematosus, evenly divided into organ-threatening (25%) and non-organ-threatening (25%) categories. The remainder of cases are cutaneous lupus (40%), mixed connective tissue disease and/or overlap syndromes (10%), and drug-induced lupus (<1%). There are seven undifferentiated connective tissue disease patients for every lupus patient [a different way to say this: “For every patient with SLE [Systemic Lupus Erythematosus], there are six or seven who display lupus-like symptoms without meeting SLE criteria”]. The true incidence and prevalence of systemic lupus in the United States are difficult to ascertain. Surveys have shown that only one in three patients told by a physician that he or she has SLE meets the American College of Rheumatology criteria.[1] […] Once thought to be a benign process, MCTD [mixed connective tissue disease] has a 20-year mortality rate of over 50%. […] Approximately one white male in 10,000, one white female in 1,000, and one African American female in 250 in the United States have SLE.[4] People of color are diagnosed with lupus more frequently than are Caucasians, but this statistic can get complicated. For example, Filipinos and Chinese are diagnosed with lupus much more frequently than are Japanese or Malays. […] Nearly 90% of persons with SLE are female, as opposed to 80% with chronic cutaneous lupus and 50% with drug-induced lupus. Most develop the disorder during their reproductive years. The female-to-male ratio is 2:1 before puberty, as high as 8:1 during years of active menstruation, and 2.3:1 for patients over the age of 60″

“Pathogenesis undergoes an often-gradual process consisting of several phases: predisposition, benign autoimmunity, prodrome, and clinical systemic lupus erythematosus. Only one person in 10 who possess lupus susceptibility genes ever develops full-blown lupus. Many individuals have “subclinical autoimmunity,” or undifferentiated connective tissue disorders where the process is attenuated. […] At least 30 susceptibility genes for SLE have been identified, and their presence varies widely depending on race, ethnicity, and geography.[1] […] Most of the lupus-associated genes have odds ratios (relative risks) of less than 2.5 (1 would indicate no predisposition), and they are only of minimal clinical value […] Lupus patients are normally fertile. However, only 67% of pregnancies in SLE patients are successful, compared to 85% in the general population.[4] […] A woman with lupus has a 2% risk of her son and a 10% risk of her daughter having lupus […]
As only 28% of monozygotic twins both have SLE, environmental factors clearly play a role. […] The development of autoantibodies precedes the first symptoms of SLE by two to nine years.”

Immune complexes and apoptotic cells circulate in the bloodstream and need to be disposed of so they do not settle in tissues (which causes inflammation) or release chemicals (e.g., cytokines, chemokines) which also promote inflammation. In SLE, this clearance fails due to a variety of mechanisms: defective phagocytosis, altered transport by complement receptors, defective regulation of T helper cells by regulatory T cells, inadequate production or function of regulatory cells that kill or suppress autoreactive B cells, low production of interleukin 2 by T cells, and defects in apoptosis that permit the survival of effector T and autoreactive B cells […] Tissue damage is produced by the deposition of circulating immune complexes into tissue, which in turn activates endothelial cells, cytokines, and chemokines. In the kidneys, this produces inflammation, followed by proliferation and ultimately fibrosis (scarring). Complement activation, overloading of the Complement Receptor 1 (CR1) transport system, antibodies to complement components […], and congenital or acquired deficiency in complement components also lead to tissue inflammation and damage. Lupus is also characterized by accelerated atherosclerosis.”

“Half of persons with systemic lupus erythematosus present with organ-threatening disease. The remaining individuals do not present with cardiopulmonary, hepatic, or renal symptoms; central nervous system (CNS) vasculitis; hemolytic anemia; or thrombocytopenia on initial evaluation. Organ involvement is relatively easy to diagnose […] On the other hand, it can often take one to two years and several physician consultations before the presence of organ-sparing lupus is ascertained. Rashes can shorten the length to time of diagnosis, but young, healthy-appearing women with non-specific symptoms of fatigue and aching are often thought to have other processes or are given psychosocial explanations. […] Lupus patients complain of a sense of malaise and fatigue. Over 90% with the disease report this to their physician, and its lack of specificity can be problematic. […] Arthralgias are present in at least 80% of SLE patients, whereas observable inflammatory arthritis involving two or more joints is found in 50% at some point in the course of the disease. […] Two-thirds of lupus patients self-report sensitivity to sunlight.[2] […] Present in a little more than one-third of lupus patients, the butterfly rash is one of the disease’s most recognizable features.”

“Oral ulcers are present in 20% of patients with SLE […] Patients with lupus may complain of pain on taking a deep breath, shortness of breath, windedness, wheezing, or chest pains. The most common problem relates to pleurisy. At autopsy, most lupus patients show evidence of pleural scarring or prior inflammation. Manifested by pain or a catching sensation on taking a deep breath, pleural symptoms are present in 60% of lupus patients, and frank effusions noted in 25%, during a lifetime. […] Seen in 1% to 9% of persons with SLE, patients with acute lupus pneumonitis (ALP) present acutely with shortness of breath and fever. Often treated telephonically as a pulmonary infection with antibiotics, the process progresses rapidly if high doses of corticosteroids are not prescribed […] ALP has an 80% mortality rate if not diagnosed within two weeks of onset; recovery is usually rapid with appropriate treatment. […] Pericardial involvement is found in 60% of lupus patients at autopsy and incidentally, and asymptomatically in 25% on 2-D echocardiogram. Frank effusions are seen in 25% during the course of disease but in fewer than 5% of patients at any given point in time […] Myocardial dysfunction (often from subclinical inflammation) is found on stress echocardiography in 40% with SLE, but only 5% to 10% ever experience frank myocarditis. […] Coronary artery disease, hypertension, insulin resistance, metabolic syndrome, hyperhomocystinemia, and hyperlipidemia are more common in lupus patients […] Most lupus patients complain of at least some intermittent cognitive impairment […] Autoimmune thyroiditis, type 1 diabetes, autoimmune adrenalitis, premenstrual disease flares, and elevated prolactin levels have increased prevalence in SLE. […] Thirty percent of individuals with SLE have some form of renal involvement; in half of these cases, it mandates organ-specific therapy […] Lupus nephritis is associated with high morbidity and mortality.”

“Lupus costs the American public approximately $20 billion a year in lost wages, disability, hospitalizations, medical visits, and medication […] Direct costs account for one-third, and indirect costs two-thirds, of this amount.[1,3] The overwhelming majority of lupus patients with non-organ-threatening disease are employed full time, while 50% with organ involvement are disabled[4] […] Part-time employment is possible for many lupus patients. Total permanent disability is not to be taken lightly. Disabled patients tend to be less independent, less socially interactive, and more depressed, and to have less self-esteem.[2] […] Currently, most patients with systemic lupus erythematosus survive at least 20 years,[1] although their quality of life is not always optimal. Historically, 40% of deaths in lupus patients with serious disease were from inflammation and occurred within two years of diagnosis. Approximately 10% of deaths took place over the following 10 years. The remaining 40% of lupus patients died 12 to 25 years after diagnosis, mostly from infections and complications of chronic steroid therapy and immunosuppression. This “bimodal” curve has been altered in the past 10 years.[2] Death due to lupus during the first two years is becoming less common; individuals with serious SLE still have a 10- to 30-year shortened life expectancy due to complications of therapy.[3] […] Patients with drug-induced lupus, chronic cutaneous lupus, and non-organ-threatening SLE without antiphospholipid antibodies have a normal survival rate. […] Approximately 5% of persons with SLE experience spontaneous remission without treatment.”

May 19, 2014 - Posted by | Books, Epidemiology, Immunology, Medicine

No comments yet.

Leave a comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.