Subacute Symptoms Research Articles

Hyperreactive malaria in expatriates returning from sub-Saharan Africa.

The extreme presentation of hyperreactive malaria is hyperreactive malarial splenomegaly syndrome (HMS). Some patients present with a less pronounced syndrome. To investigate whether the degree of splenomegaly correlates with the degree of immune stimulation, whether prophylaxis or recent treatment play a role, and whether short therapy alone is effective, we examined retrospectively the medical records of expatriates with exposure to P. falciparum who attended our outpatient department from 1986 to 1997, particularly subacute symptoms or signs, strongly elevated malarial antibodies and elevated total serum IgM. We analysed duration of stay, prophlyaxis intake, spleen size, serum IgM levels and response to antimalarial treatment. Serum IgM levels were significantly higher in patients with larger splenomegaly. The use of chloroquine alone as treatment for presumptive or proved malaria attacks was correlated with larger spleen size. Short adequate antimalarial therapy resulted in marked improvement or complete recovery. In nine patients the hyperreactive response reappeared after re-exposure, in four of them twice. We conclude that patients with subacute symptoms but without gross splenomegaly may have very high levels of IgM and malarial antibodies, and relapse on re-exposure, suggesting the existence of a variant of the hyperreactive malarial splenomegaly syndrome without gross splenomegaly.

Thirteenth Annual Meeting of the Society for Pediatric Anesthesia, Dallas, Texas, October 8, 1999

Thirteenth Annual Meeting of the Society for Pediatric Anesthesia, Dallas, Texas, October 8, 1999

L'allergie aux hydrolysats de protéines du lait de vache. À propos de huit cas

The use of extensively hydrolyzed protein formulas is the best alternative for children with cow's milk allergy, though cases of allergies to hydrolyzed proteins have been reported. The aim of this study was to clarify from our experience the diagnostic, evolutive and therapeutic aspects of allergies to extensively hydrolyzed protein formulas. We report eight cases of allergy to extensively hydrolyzed protein formulas seen between 1985 and 1998. The diagnostic criteria for allergy were either the appearance of immediate anaphylactic reactions after the ingestion of protein hydrolysate or a positive challenge test with the protein hydrolysate. Four children developed immediate anaphylactic symptoms after ingesting protein hydrolysate, and four children demonstrated subacute or chronic gastrointestinal symptoms. All children who developed acute anaphylactic symptoms had positive skin tests and specific IgF, antibodies (RAST) to cow's milk and/or hydrolyzed proteins. Conversely, in the four children with chronic gastrointestinal symptoms, skin tests and specific IgE antibodies were negative in three cases, but intestinal histology was abnormal in all of them when they were fed with a protein hydrolysate; this became normal after excluding the hydrolysate (data available in only two cases). Three children tolerated another protein hydrolysate form (whey vs. casein), four children had a favourable outcome when fed with human milk, and an amino-acid-based formula was successfully used in the most recent case. Nonhydrolyzed cow's milk proteins were tolerated after the age of 18 months in six children. Other atopic symptoms were observed in six children. Allergy to cow's milk protein hydrolysate is rare. The diagnosis is usually easy in children who develop acute anaphylactic symptoms, though intestinal histology is generally necessary for the diagnosis of allergy with chronic gastrointestinal symptoms. Treatment is based on the use of either another protein hydrolysate form (whey vs. casein) or an amino-acid-based formula.

Bacteriological studies of blood, tissue fluid, lymph and lymph nodes in patients with acute dermatolymphangioadenitis (DLA) in course of ‘filarial’ lymphedema

Filarial lymphedema is complicated by frequent episodes of dermatolymphangioadenitis (DLA). Severe systemic symptoms during attacks of DLA resemble those of septicemia. The question we asked was whether bacterial isolates can be found in the peripheral blood of patients during the episodes of DLA. Out of 100 patients referred to us with ‘filarial’ lymphedema 14 displayed acute and five subacute symptoms of DLA. All were on admission blood microfilariae negative but had a positive test in the past. Blood bacterial isolates were found in nine cases, four acute (21%) and five subacute (26%). In 10 acute cases blood cultures were found negative. Six blood isolates belonged to Bacilli, four to Cocci and one was Sarcina. To identify the sites of origin of bacterial dissemination, swabs taken from the calf skin biopsy wounds and tissue fluid, lymph and lymph node specimens were cultured. Swabs from the calf skin biopsy wound contained isolates in nine (47%) cases. They were Bacilli in nine, Cocci in three, Acinetobacter and Erwinia in two cases. Tissue fluid was collected from 10 patients and contained Bacilli in four (40%) and Staphylococci in three (30%). Lymph was drained in four patients and contained isolates in all samples (100%). They were Staphylococcus epidermis, xylosus and aureus, Acinetobacter, Bacillus subtilis and Sarcina. Three lymph nodes were biopsied and contained Staphylococcus chromogenes, xylosus, Enterococcus and Bacillus cereus. In six cases the same phenotypically defined species of bacteria were found in blood and limb tissues or fluids. In the ‘control’ group of patients with lymphedema without acute or subacute changes all blood cultures were negative. Interestingly, swabs from biopsy wound of these patients contained isolates in 80%, tissue fluid in 68%, lymph in 70% and lymph nodes in 58% of cases. In healthy controls, tissue fluid did not contain bacteria, and lymph isolates were found only in 12% of cases. This study demonstrates that patients with acute episodes of DLA reveal bacteriemia in a high percentage of cases. Diversity of blood and tissue bacterial isolates in these patients points to a breakdown of the skin immune barrier in lymphedema and subsequently indiscriminate bacterial colonization of deep tissues and spread to an blood circulation.

Maternal cigarette smoking during pregnancy is an independent predictor for symptoms of middle ear disease at five years' postdelivery.

Although an increasing body of literature has demonstrated a link between in utero exposure to cigarette smoke and childhood morbidity, the extent to which such exposure is associated with middle ear disease (MED) is less certain. We hypothesized that in utero exposure to cigarette smoke was associated with an increased risk of MED and aimed to calculate the proportion of disease at 5 years' postdelivery attributable to cigarette exposure during pregnancy. Methods. At their first antenatal session, 8556 women were enrolled in a prospective study of pregnancy. Mothers were followed during pregnancy, at birth, at 6 months' and at 5 years' postdelivery and completed a detailed questionnaire aimed at assessing the frequency of acute (<1 month) and subacute (1-3 months) symptoms of MED and ear surgery. The relationship between MED and smoking status during pregnancy was then examined and subsequently adjusted simultaneously for smoking status at other times and for other potentially confounding variables. Results. In the adjusted analyses, acute ear infections were associated with consumption of 1 to 9 cigarettes (OR: 1.6; 95% CI: 1.1-2.5), 10 to 19 cigarettes (OR: 2.6; 95% CI: 1. 6-4.2) and 20+ cigarettes (OR: 3.3; 95% CI: 1.9-5.9) per day at the first clinic visit. For subacute ear infections, an association was present with consumption of 10 to 19 cigarettes (OR: 2.6; 95% CI: 1. 4-5.0) and 20+ cigarettes (OR: 2.8; 95% CI: 1.3-6.0) at the first clinic visit. In utero exposure to 20+ cigarettes per day at the first clinic visit was also associated with an increased risk of ear surgery by 5 years' postdelivery (OR: 2.9; 95% CI: 1.3-6.6). These associations were independent of smoking at 6 months and at 5 years, age and gender of the child, breastfeeding history, maternal age, maternal education, maternal employment at 5 years, marital status at 5 years, socioeconomic status, use of day care, and the number of siblings or children in the household. A population attributable risk percent at 5 years of 39.4% for acute ear infections, 37.9% for subacute ear infections, and 30.0% for previous ear surgery was found for in utero exposure to cigarette smoke at the first clinic visit. Conclusions. Smoking at the first clinic visit was associated with an increased risk of MED and ear surgery at 5 years of age. The frequency of maternal smoking in the general population gives rise to a high population attributable risk percent for MED. Therefore, it is a significant contributor to childhood morbidity and provides another reason why women should be encouraged to avoid smoking during pregnancy.

Thoracic outlet syndrome: influence of personal history and surgical technique on long-term results.

Long-term results after surgery for thoracic outlet syndrome (TOS) are reviewed in terms of personal histories and surgical techniques. Forty-eight operations were performed in 37 patients. In 21 instances, the picture was one of ordinary TOS, in eight TOS was traumatic and in nine the picture was sub-acute. Cervical ribs were excised through a supraclavicular approach (in seven cases), and first ribs through transthoracic, transaxillary or supraclavicular approaches (in 25, 15 or one, respectively). Long-term follow-up was obtained in 41 cases and averaged 11.7 years. Surgical decompression was successful in 28 cases (68%), including all patients with traumatic TOS (8/8) and seven with sub-acute symptoms (7/9). Outcome was good in five of seven supraclavicular cervical rib resections, and in 23 of 34 first rib excisions. First rib resections performed transaxillary had shorter post-operative stays, fewer complications. Surgical decompression is more successful when TOS is traumatic or sub-acute. When involved, a cervical rib can be resected through a supraclavicular approach, since the procedure is easy and has little morbidity. The transaxillary approach should be preferred for first rib resections because of shorter post-operative stays and fewer complications than after the transthoracic approach.

A survey concerning the equine fescue toxicosis malady

The objective of this research was to determine the scope of equine fescue toxicosis, current procedures to control the disease, and to gain veterinary insight to possible new therapies. A survey was developed with help form experts in the area of fescue toxicosis. From a list of members of the American Veterinary Medical Association (AVMA), a sample was obtained by selecting large animal/equine veterinarians from states where fescue toxicosis is common. These states included: Alabama, Arkansas, Georgia, Illinois, Indiana, Kentucky, Missouri, Mississippi, North Carolina, Ohio, South Carolina, Tennessee, Virginia, and West Virginia. One-fifteenth of the veterinarians (515 total) were mailed questionnaires; 207 responded. Veterinarians were grouped into regions based on latitude. Region 1 included veterinarians practicing north of 39.0° latitude; Region 2 included veterinarians practicing between 36.5° and 39.0° latitude; and Region 3 included veterinarians practicing south of 36.5° latitude. A majority of horse pasture in the area of the survey is comprised of at least 50% fescue, with approximately 70% of the pasture being at least partially comprised, of fescue. Almost 50% of the brood mares in the area of the survey are exposed to endophyte-infected fescue. Many gravid brood mares in the area of the survey were suffering from acute and subacute symptoms, with over 43% warranting some kind of management technique to prevent toxicity from occurring. A large majority of veterinarians in the area of the survey feel that fescue toxicosis is, to some level, a problem. Current management techniques can be tedious and expensive. New management techniques and/or therapies are needed to handle the problems associated with equine fescue toxicosis. A large majority of veterinarians in the area of the survey feel an effective drug therapy would be valuable in treating equine fescue toxicosis. If a drug therapy were developed, a daily feed additive or an oral gel would be the most popular method of dosing with veterinarians. As a result of trends noticed in the rates of equine fescue toxicosis in different areas, statistical analyses were conducted on data generated from this survey along regions that seemed to have different infection rates. There was no difference (P>0.05) in levels of fescue in pastures, mare exposure to the endophyte, and mare expression of acute or subacute symptoms between regions 2 and 3. There was a difference (P<0.05) between region 1 and regions 2 and 3 for all of the factors tested except for number of mares seen by veterinarians.

Episode of toxic gas exposure in sewer workers.

OBJECTIVES: Sewer workers are used to unpleasant smells, but may be required to investigate unusual ones. Twenty six men were involved in investigation of episodes of such a smell after...

Acute lumbosacral plexopathy during and after preoperative radiotherapy of rectal adenocarcinoma

The benefit of preoperative radiotherapy of adenocarcinoma of the rectum with respect to a reduced local recurrence rate and an improved survival should be weighed against adverse effects. For 14 years a three-beam, isocentric technique was employed at our hospital to deliver five fractions (5.0 or 5.1 Gy), over 5 or 7 days preoperatively, to patients with rectal cancer which was considered primarily resectable. The adverse effects of the radiotherapy were few, but acute pain and subacute neurological symptoms and signs did occur. An apparent increase in the frequency of these symptoms/signs was noted during 1993. The pain and neurological symptoms are described in case reports and the individual treatments are reviewed. The three-beam technique was analyzed in detail with individual, CT-based, three-dimensional dose-planning and dose distributions in the vicinity of the lumbar nerve plexus are presented. The major result of this analysis showed that technical errors could be excluded, that human errors were unlikely, and that the culprit probably was an unexpected sensitivity to marginal changes in the daily dose and unknown or unexpected radiosensitizing effects of concurrent diseases or medication.

Can CT distinguish hypersensitivity pneumonitis from idiopathic pulmonary fibrosis?

The clinical management of patients with idiopathic pulmonary fibrosis differs markedly from that of patients with hypersensitivity pneumonitis. However, the two diseases often cannot be differentiated on clinical grounds. The purpose of this study was to establish whether CT can be used to make the distinction. Thirty-six patients with idiopathic pulmonary fibrosis and 27 patients with hypersensitivity pneumonitis were studied. All diagnoses were confirmed or supported by open lung biopsy. Three of the patients with idiopathic pulmonary fibrosis had desquamative interstitial pneumonia, and the remainder had usual interstitial pneumonia. In 19 of the 27 patients with hypersensitivity pneumonitis, the disease was chronic (symptoms lasting more than 1 year), while eight had acute or subacute symptoms. Two radiologists, who had not previously seen any of the cases and were blinded to the diagnosis, reviewed the CT images by consensus. The extent and distribution of CT features (including ground-glass attenuation, honeycombing, and micronodules) were recorded. In each case, a CT diagnosis was made, and the level of diagnostic confidence was recorded. A CT diagnosis was made with a high level of confidence in 39 (62%) of 63 patients. In these patients, the CT diagnosis was correct in 35 cases (90%): 23 of 26 patients with a CT diagnosis of idiopathic pulmonary fibrosis and 12 of 13 patients with a CT diagnosis of hypersensitivity pneumonitis. In the three patients with desquamative interstitial pneumonia, the CT diagnoses were probable hypersensitivity pneumonitis in two cases and definite hypersensitivity pneumonitis in one case. Of the 19 patients with chronic hypersensitivity pneumonitis, only seven had a definite diagnosis of hypersensitivity pneumonitis based on CT findings; three had a definite diagnosis of idiopathic pulmonary fibrosis. The patients with idiopathic pulmonary fibrosis and usual interstitial pneumonia were more likely to have honeycombing and peripheral or lower lung zone predominance of disease, and less likely to have micronodules, than were patients with chronic hypersensitivity pneumonitis. The patients with idiopathic pulmonary fibrosis and desquamative interstitial pneumonia had widespread ground-glass opacity indistinguishable from some cases of acute or subacute hypersensitivity pneumonitis. Our results show that CT can be used to distinguish idiopathic pulmonary fibrosis from hypersensitivity pneumonitis in most but not all cases. Desquamative interstitial pneumonia cannot reliably be distinguished from acute or subacute hypersensitivity pneumonitis. Chronic hypersensitivity pneumonitis may have findings identical to those of usual interstitial pneumonia. Lung biopsy should still be considered the gold standard for diagnosis of interstitial lung disease.

Intestinal Endometriosis Masquerading as Common Digestive Disorders

Intestinal endometriosis mimics a wide variety of inflammatory, infectious, or neoplastic digestive diseases. To alert clinicians to its diverse manifestations, we describe nine patients who required laparotomy. The underlying diagnosis was elusive initially. In no case were symptoms clearly cyclic or temporally related to phases of the menstrual cycle. Presenting complaints included acute or subacute lower abdominal pain (three patients), hematochezia (two patients), signs or symptoms of small-bowel obstruction (two patients), peritonitis (one patient), and a partially obstructing sigmoid lesion (one patient). The findings of barium enema were nondiagnostic in the five cases in which it was performed. Surgery was needed in each case; indications included inability to exclude carcinoma (two patients), small-bowel obstruction (two patients), diffuse peritonitis (one patient), persistent colonic obstruction (one patient), pericolonic abscess (one patient), and intractable pain (one patient). Intestinal endometriosis has a diverse clinical spectrum, with nonspecific features in many patients. This disease should be considered during the evaluation of unexplained digestive complaints in women of childbearing years.

Neurological and Psychiatric Adverse Effects of Immunological Therapy

Immunological therapy with cytokines can cause acute, subacute, delayed and, occasionally, irreversible toxicity to the CNS. Neurotoxic adverse effects are manifested by changes in cognitive, motor and emotional functioning. Although these changes are sometimes global in nature, most subacute neurotoxic symptoms attributable to interferon-α, interleukin-2 and tumour necrosis factor are specific to frontal-subcortical dysfunction and involve specific neuroanatomical and neurochemical systems. The symptoms observed typically include memory deficits, difficulties with motivation and flexible thinking (frontal lobe executive function) and motor coordination. Reasoning, language functions and visual perception are generally not affected. Depression and other psychiatric presentations are common and appear to be due to the biochemical changes induced by cytokines rather than psychological reactions to the illness for which the agents are administered. The mechanism of action of cytokines on brain function may include alterations in neurotransmitter function (mostly involving opioid and dopaminergic systems), induction of the release of neuroendocrine hormones and of other cytokines. Improved understanding of the mechanism of cytokine action in the brain is guiding the development of treatment interventions to reduce or eliminate CNS toxicity without sacrificing therapeutic efficacy. In addition, studies of cytokine neurotoxicity have advanced our knowledge of the normal role of these agents in the CNS.

Solitary ischaemic small bowel stenosis

A case of a solitary short ischaemic stenosis of the small bowel is presented and the literature reviewed. An ischaemic segmental stenosis of the small bowel is a rare lesion, but can lead to acute or subacute obstructive symptoms. A well conducted small bowel enteroclysis is the diagnostic modality of choice in such a case, which may require surgical resection after the diagnosis is made.

Reduced Severity of Eosinophilia-Myalgia Syndrome Associated With the Consumption of Vitamin-Containing Supplements Before Illness

To determine if the severity of subacute symptoms in eosinophilia-myalgia syndrome (EMS) was affected by medical history or use of nutritional supplements other than tryptophan before illness. A case-control study was conducted of EMS cases systematically sampled from all those reported to a statewide surveillance system in California in 1989. Excluding two previous EMS-related deaths, interviews were completed in 73% (57/78) of the eligible case patients sampled. The severity of any myalgia(s), dyspnea, or walking impairment during each of the first 3 months of EMS was quantified by means of self-reported integer scores ranging from 0 (asymptomatic) to 10 (severe symptoms). Case patients in the top tercile of combined, unweighted monthly scores were defined as having severe symptoms. All interviewees (57 of 57) had consumed supplemental tryptophan before illness; 89% (51/57) were female. The odds of severe symptoms were not significantly associated with gender, age, previous antidepressant use, or cumulative amounts of supplemental tryptophan consumed before or after EMS onset (P > .1). Previous consumption of any multivitamin(s), however, was associated with significantly lower odds of severe symptoms (adjusted odds ratio, 0.05; 95% confidence limits, 0.007, 0.4; P = .006). The consumption of multivitamin-containing supplements before EMS appears to have modified the severity of subacute symptoms in this sample of cases from California.

Neurosyphilis in HIV carriers: MR findings in six patients.

Neurosyphilis, a sexually transmitted disease that can cause neurologic damage, has become increasingly prevalent in the AIDS era. HIV carriers can contract neurosyphilis without the presence of other concurrent opportunistic infections. Because MR findings of neurosyphilis are seldom reported, we retrospectively reviewed and evaluated contrast-enhanced MR images of six young (average age, 33 years) HIV-positive men with high serum and CSF VDRL titers indicative of neurosyphilis. All six patients tested negative for concurrent opportunistic infections. Five patients had acute or subacute strokelike symptoms involving the basal ganglia or middle cerebral arteries; one had a parietal convexity mass mimicking meningioma with headache and ataxia. Contrast-enhanced MR images showed patchy enhancement involving the basal ganglia and middle cerebral artery territories in the first five patients and the convexity mass in the sixth patient. On the basis of brain biopsy, a convexity mass was diagnosed in the patient with syphilitic gumma. The imaging findings of the remaining five patients represented ischemic infarct caused by meningovascular syphilis. After penicillin treatment, serum and CSF VDRL titers decreased, and neurologic signs and symptoms improved in all six patients. A follow-up MR study in the patient with the gumma showed that the lesion resolved almost completely. In young HIV patients with stroke symptoms or a convexity mass, neurosyphilis should be considered. Contrast-enhanced MR can reveal the extent of involvement by neurosyphilis and should be used to facilitate diagnosis and proper treatment.

Misdiagnosis of Rheumatoid Arthritis in an Elderly Woman with Gout

Polyarticular gout may be misdiagnosed in the elderly. This reflects the confusing clinical presentation of "diuretic gout" in the elderly, characterized by polyarticular onset, subacute symptoms, hand involvement, and early development of tophi. A misdiagnosis of rheumatoid arthritis can lead to poor treatment of gout, failure to recognize underlying renal insufficiency, and associated cardiac risks. Hyperuricemia may reflect systemic ATP depletion in acutely ill patients and thus represents a predictor for mortality. Medical treatment of polyarticular gout in elderly patients with compromised cardiac and renal function requires recognition of the clinical profile and consideration of the increased toxicity from standard therapies.

Cardiac Localization of Eosinophil-Granule Major Basic Protein in Acute Necrotizing Myocarditis

THE association of eosinophilia and endomyocarditis has been well documented. A form of Loffler's endocarditis,1 characterized by eosinophilic pancarditis, muscle necrosis, and arteritis, is usually a feature of certain systemic diseases, including the hypereosinophilic syndrome,2 3 4 eosinophilic leukemia,5 polyarteritis nodosa,6 , 7 drug-induced hypersensitivity,8 bronchial asthma,9 10 11 biliary tract carcinoma,12 and parasitic disease.13 The cardiac involvement is characterized by a subacute course and symptoms of congestive heart failure. Treatment with glucocorticoids and cytotoxic agents is effective.14 Fulminant acute necrotizing eosinophilic myocarditis occurring in the absence of notable extracardiac disease has been reported only rarely.15 The disease has a short course and is rapidly fatal. . . .

Vascular Malformations of the Spinal Cord and Dura

Current techniques of diagnosis and treatment allow for earlier detection, precise delineation of the vascular anatomy, and, most important, successful treatment of most patients with spinal AVMs. Magnetic resonance imaging is useful in the initial assessment of patients with progressive myelopathy but cannot replace myelography or arteriography in screening patients who may have a spinal AVM. The most common variety of spinal AVM is a dural arteriovenous fistula. Dural arteriovenous fistulas cause cord injury by producing venous congestion, and symptoms can be reversed by elimination of venous congestion of the spinal cord. Dural arteriovenous fistulas can be treated successfully by interrupting the arteriovenous fistula either in the dura or by disconnecting the dural fistula from the coronal venous plexus in the subarachnoid space. This can be done by interrupting the medullary vein that drains the arterial blood from the dural fistula into the coronal venous plexus of the spinal cord. Stripping of the engorged venous network on the surface of the spinal cord is unwarranted and may cause further cord injury. In dural arteriovenous fistulas embolization is often beneficial in patients with acute neurologic deterioration, to permit time for stabilization and improvement in spinal cord hemodynamics and in cord function before neurosurgical intervention is undertaken. Embolization also may be indicated in patients with intradural spinal AVMs in which surgery cannot be performed safely. Although embolic occlusion does not permanently occlude most intradural AVMs, it often permits stabilization of neurologic function and may be repeated later if neurologic dysfunction returns or progresses. Although the outcome after treatment is dependent on the type and location of the spinal AVM, as in most treatable neurologic disorders the functional outcome of patients with spinal AVMs is directly related to their neurologic condition at the time of treatment. Patients with minimal dysfunction, and with easily accessible AVMs, such as dural arteriovenous fistulas, have the greatest chance for useful recovery or stabilization. Since these patients represent the largest number of patients with spinal AVMs, they must be diagnosed and treated early to achieve the best possible outcome.

Nonsurgical treatment of posterior fossa epidural hematoma

The recommended treatment for posterior fossa epidural hematoma has been prompt surgical evacuation. We report 2 patients who were treated conservatively. Both patients were younger than 10 years of age and developed subacute symptoms and signs. Serial computed tomography demonstrated complete resolution of the hematomas and no development of hydrocephalus during nonsurgical treatment. They recovered well without any neurologic deficits. In order to evaluate an indicative factor for nonsurgical treatment in young children with posterior fossa epidural hematoma, we review both of our patients and 36 well-documented patients from the literature, all of whom were younger than 10 years of age. The results demonstrate that the development of hydrocephalus is a critical factor in clinical progression. Nonsurgical management can be applied in these circumstances until spontaneous resolution of the hematoma unless early signs of medullary compression appear acutely after head trauma or serial computed tomography demonstrates the development of hydrocephalus followed by medullary compression.

Treatment of acute hepatic porphyria with hematin

The efficacy of hematin has been evaluated in eight patients with acute intermittent porphyria: six with acute attacks and two with chronic subacute symptoms. Hematin suppressed the chemical signs of porphyria in all patients and the symptoms in those with acute attacks. The clinical response to hematin occurred uniformly on the third or fourth day of treatment, suggesting that a stereotypic response to this form of therapy can be defined. Hematin had no effect on chronic subacute symptoms. The indications for hematin therapy, its rationale and the details of its administration are reviewed.