Algoneurodystrophy following herpes zoster

The clinical relevance of complex regional pain syndrome type I: The Emperor's New Clothes

The management of patients with chronic pain is a nearly daily challenge to rheumatologists, neurologists, orthopedic surgeons, pain specialists and indeed a issue in nearly every clinical practice. Among the myriad of causes of pain are often included a unique syndrome, generally referred to as complex regional pain syndrome type I (CRPS). Unfortunately CRPS I has become a catch all phase and there are serious questions on whether it exists at all; this has led to an extraordinary number of poorly defined diagnostic criteria. It has also led to an etiologic quagmire that includes features as diverse as autoimmunity to simple trauma. These, in turn, have led to overdiagnosis and often overzealous use of pain medications, including narcotics. In a previous paper, we raised the issue of whether CRPS type I reflected a valid diagnosis. Indeed, the diagnostic criteria for CRPS I, and therefore the diagnosis itself, is unreliable for a number of reasons: 1) the underlying pathophysiology of the signs and symptoms of CPRS I are not biologically plausible; 2) there are no consistent laboratory or imaging testing available; 3) the signs and symptoms fluctuate over time without a medical explanation; 4) the definitions of most studies are derived from statistical analysis with little consideration to required sample size, i.e. power calculations; 5) interobserver reliability in the assessment of the signs and symptoms are often only fair to moderate, and agreement on the diagnosis of "CRPS I" is poor. Even physicians who still believe in the concept of "CRPS I" admit that it is vastly overdiagnosed and has become a diagnosis of last resort, often without a complete differential diagnosis and an alternative explanation. Finally, one of the most convincing arguments that there is no clinical entity as "CRPS I" comes from the enormous heterogeneity in sign and symptom profiles and the heterogeneity of pathophysiological mechanisms postulated. This observation is underscored by the diversity of responses among "CRPS I" patients to essentially all treatment modalities. It has even led to the concept that the signs and symptoms of CRPS can spread throughout the body, as if it is an infectious disease, without any medical plausible explanation. If true progress is to be made in helping patients with pain, it will require entirely new and different concepts and abandoning CRPS I as a legitimate diagnosis.

A case of pain, motor impairment, and swelling of the arm after acute herpes zoster infection

Complex regional pain syndrome (CRPS) and postherpetic neuralgia (PHN) represent neuropathic pain syndromes that may appear with similar clinical signs and symptoms. Medical history and clinical distribution of symptoms and signs (PHN typically at the thorax; CRPS typically at the limbs) is obvious in most cases, helping to discriminate between both disorders. Here, we present a patient suffering from CRPS II following PHN of one upper extremity. This case demonstrates that both etiology and part of the body affected by a neuropathy influence the pain phenotype.

Complex regional pain syndrome-like symptoms during herpes zoster

Complex Regional Pain Syndrome (CRPS) associated with herpes zoster (HZ) was first reported by Sudeck in 1901 (Sudeck, 1901) and is recognized clinically. However, only 13 cases have been published in the literature, and nothing is known about the incidence, prevalence, or natural history (Chester, 1992; Foster et al., 1989; Grosslight et al., 1986; Ketz and Schliack,1968; Kishimoto et al., 1995; Querol and Cisneros, 2001; Sudeck, 1901; Visitsunthorn and Prete, 1981). The aim of the present study was to determine the prevalence of CRPS-like symptoms in a prospectively gathered cohort of subjects with HZ and to follow the natural history of their pain and sensory disturbance during the first 6 months after onset of HZ. Subjects were evaluated at four time points after HZ: 2-6 weeks, 6-8 weeks, 3 months, and 6 months. Only subjects aged 50 or older with pain VAS ratings of >/=20/100 at 2-6 weeks were eligible. The first (screening) visit included a neurological and physical examination that was updated at each subsequent visit. Assessments included ratings of pain intensity, allodynia severity, and rash severity. The neurological exam included determination of presence or absence of the following CRPS-like symptoms: (1) increased sweating, (2) color changes, (3) skin temperature changes, (4) weakness of the affected area based on physical exam, (5) edema, and (6) extension of CRPS-like symptoms outside the affected dermatome. For subjects with HZ in dermatomes that can include the limbs (C4-T2 and L1-S2), extremity involvement was considered present if allodynia or rash extended beyond the neck of the humerus (upper extremity), the inguinal ligament (anterior lower extremity), or gluteal sulcus (posterior lower extremity). Involvement of the extremity was considered proximal if neither HZ rash nor allodynia extended past the elbow (upper extremity) or knee (lower extremity). Of the first 75 subjects recruited, 25 had HZ outbreaks in dermatomes that extended into the extremities (C4-T2 and L1-S2). In this group, 8 subjects had no extremity involvement, 8 had proximal extremity involvement, and 9 had distal extremity involvement. Subjects with distal extremity HZ reported more pain across the four visits (p < 0.05). At 3 months, more subjects with distal extremity involvement met criteria for PHN (8 out of 9, 89%), while only 4 out of 8 (50%) with proximal involvement and 2 out of 8 (25%) of subjects without extremity involvement met criteria for PHN (Chi-square test: p < 0.05). Only 25 out of the remaining 50 (50%) subjects with outbreaks in dermatomes that do not include the extremities met criteria for PHN at 3 months (Chi-square test: p < 0.05). Six months after onset of HZ, 6 out of 9 subjects with distal extremity involvement met PHN criteria compared with 2 out of 8 (25%) with proximal involvement and 2 out of 8 (25%) without extremity involvement (Chi-square test: p = 0.12). Fifteen out of 50 (30%) subjects with outbreaks in dermatomes that do not include the extremities met criteria for PHN (Chi-square test: p < 0.05). No subject had all six CRPS-like symptoms. Of the 17 subjects with extremity involvement, 9 subjects had '0-2 CRPS-like symptoms' and 8 had '3-5 CRPS-like symptoms'. None of the eight subjects without extremity involvement had any CRPS-like symptoms. Of the 50 subjects with HZ outside the extremity, only one had abdominal weakness. Pain ratings were higher in subjects with '3-5 CRPS-like symptoms'. More subjects with '3-5 CRPS-like symptoms' met criteria for PHN at 3 months (7 out of 8, 88%), compared to 5 out of 9 (55%) of subjects with '0-2 CRPS-like symptoms' (p = 0.07). At 6 months, 2 out of 9 (22%) of subjects with '0-2 CRPS-like symptoms' met criteria for PHN, compared with 6 out of 8 (75%) of subjects with '3-5 CRPS-like symptoms' (Chi-square test: p < 0.03). Two case-reports are presented. In summary, the occurrence of CRPS-like symptoms is common in subjects with HZ outbreaks affecting the extremity, particularly if the distal extremity is involved. It is uncertain if the pathophysiology underlying the CRPS-like symptoms observed in this study is similar to that of CRPS from other causes, or if it is relatively specific to HZ. Development of PHN is common in subjects who have experienced CRPS-like symptoms. More aggressive preventive treatments may be justified in this high-risk subset of HZ subjects to prevent development of PHN. Prospective randomized controlled studies are needed to determine which subjects are most likely to benefit and when treatment should begin.

Reflex sympathetic dystrophy with hidradenitis suppurativa exacerbation: a case report

Reflex sympathetic dystrophy (RSD) or complex regional pain syndrome type 1, is characterized by spontaneous pain or allodynia and hyperalgesia disproportionate to the inciting event, multiperipheral nerve involvement, edema, vasomotor or sudomotor change, and possible loss of function. It has been described in relation to various insults, including a number of infectious and inflammatory conditions. We report a case of a patient who developed RSD 1 week after an exacerbation of hidradenitis suppurativa, a rare chronic inflammatory disease of apocrine sweat glands. The patient responded well to a combination of range-of-motion exercises, thermal modalities, and oral steroids. Hidradenitis suppurativa should be considered when searching for an etiology of new onset RSD.