SCUAD and chronic rhinosinusitis. Reinforcing hypothesis driven research in difficult cases

BACKGROUND

Our objective is to present recent research findings on recalcitrant chronic rhinosinusitis (CRS) in relation to "Severe Chronic Upper Airway Disease" (SCUAD).

METHODOLOGY

Literature review using Medline and Em base databases (search terms 'chronic rhinosinusitis'; "chronic sinusitis" or"Severe Chronic Upper Airway Disease") limited to articles published in the English language.

RESULTS

Complex pathophysiological mechanisms characterize various forms of chronic rhinitis and rhinosinusitis (CRS), where inflammation persists in spite of adequate medical treatment. In these cases, a multifactorial etiology often underlies the development of sino-nasal inflammation. The interaction between chronic upper and lower airway inflammation via neurogenic and systemic pathways may complicate the therapy of these patients, and lead to insufficient symptom control.

CONCLUSION

The recently introduced definition of"Severe Chronic Upper Airway Disease" (SCUAD) increases awareness of those patients with persistent inflammation and symptoms despite guideline-driven pharmacologic treatment. The concept of SCUAD may prove helpful in directing research towards clarifying the definition, diagnosis and pathophysiology of rhinitis and rhinosinusitis,their limits and overlap. In this review, a hypothesis on SCUAD immunopathology is also presented.

The potential roles of strigolactones and brassinosteroids in the autoregulation of nodulation pathway

BACKGROUND AND AIMS

The number of nodules formed on a legume root system is under the strict genetic control of the autoregulation of nodulation (AON) pathway. Plant hormones are thought to play a role in AON; however, the involvement of two hormones recently described as having a largely positive role in nodulation, strigolactones and brassinosteroids, has not been examined in the AON process.

METHODS

A genetic approach was used to examine if strigolactones or brassinosteroids interact with the AON system in pea (Pisum sativum). Double mutants between shoot-acting (Psclv2, Psnark) and root-acting (Psrdn1) mutants of the AON pathway and strigolactone-deficient (Psccd8) or brassinosteroid-deficient (lk) mutants were generated and assessed for various aspects of nodulation. Strigolactone production by AON mutant roots was also investigated.

KEY RESULTS

Supernodulation of the roots was observed in both brassinosteroid- and strigolactone-deficient AON double-mutant plants. This is despite the fact that the shoots of these plants displayed classic strigolactone-deficient (increased shoot branching) or brassinosteroid-deficient (extreme dwarf) phenotypes. No consistent effect of disruption of the AON pathway on strigolactone production was found, but root-acting Psrdn1 mutants did produce significantly more strigolactones.

CONCLUSIONS

No evidence was found that strigolactones or brassinosteroids act downstream of the AON genes examined. While in pea the AON mutants are epistatic to brassinosteroid and strigolactone synthesis genes, we argue that these hormones are likely to act independently of the AON system, having a role in the promotion of nodule formation.

New insights into the role of PML in tumour suppression

The PML gene is involved in the t(15;17) translocation of acute promyelocytic leukaemia (APL), which generates the oncogenic fusion protein PML (promyelocytic leukaemia protein)-retinoic acid receptor alpha. The PML protein localises to a subnuclear structure called the PML nuclear domain (PML-ND), of which PML is the essential structural component. In APL, PML-NDs are disrupted, thus implicating these structures in the pathogenesis of this leukaemia. Unexpectedly, recent studies indicate that PML and the PML-ND play a tumour suppressive role in several different types of human neoplasms in addition to APL. Because of PML's extreme versatility and involvement in multiple cellular pathways, understanding the mechanisms underlying its function, and therefore role in tumour suppression, has been a challenging task. In this review, we attempt to critically appraise the more recent advances in this field and propose new avenues of investigation.

Care for adolescent pregnancy and childbirth

The rise in adolescent pregnancy in the 20th century has been influenced by declining age at menarche, increased schooling, delay of marriage, inadequate contraception and poverty. The main problems are preterm labor, hypertensive disease, anemia, more severe forms of malaria, obstructed labor in very young girls in some regions, poor maternal nutrition and poor breastfeeding. In many regions HIV infection is an important problem. The infants of adolescent mothers are more prone to low birth weight and increased neonatal mortality and morbidity. Antenatal care is often inadequate. The most important problem is the increased incidence of preterm labor and delivery, the youngest age groups running the highest risk. Technically, care of adolescents during labor need not differ from care of older women; most adolescents are not at increased risk during labor, although, they are more in need of empathic support. Generally, care of pregnant adolescents should be adjusted to their specific needs.

Unsafe abortion in adolescents

Every year, an estimated 2.0-4.4 million adolescents resort to abortion. In comparison with adults, adolescents are more likely to delay the abortion, resort to unskilled persons to perform it, use dangerous methods and present late when complications arise. Adolescents are also more likely to experience complications. Consequently, adolescents seeking abortion or presenting with complications of abortion should be considered as a medical emergency. Issues requiring special attention in the management of abortion complications in adolescents are identified. Approaches to adolescent abortion should involve all levels of the health care system, as well as the community, and should include not only management of the consequences of unsafe abortion, but also post-abortion contraception and counseling. Prevention of unwanted pregnancy by providing information on sexuality, ensuring that reproductive health services are adolescent-friendly, creating a supportive environment, building young people's social and decision-making skills, and offering counseling in times of crisis are highlighted.

A study of the effect of nasal steroid sprays in perennial allergic rhinitis patients with rhinitis medicamentosa

OBJECTIVE

To determine if rebound congestion can be reduced with concomitant nasal steroid spray usage.

STUDY DESIGN AND SETTING

Randomized, double blind, controlled single center study.

PARTICIPANTS

Twenty subjects with perennial allergic rhinitis with nasal congestion.

INTERVENTION

All subjects received 3 weeks of twice-daily oxymetazoline. After 2 weeks, subjects were randomized to 2 additional weeks of concomitant budesonide aqueous nasal spray (n = 9) or placebo (n = 10). In the sixth week, all sprays were stopped.

RESULTS

Both groups showed subjective and objective evidence of rebound congestion 24 hours after cessation of oxymetazoline (P < 0.05). Subjective rebound congestion resolved in 48 hours in the budesonide aqueous nasal spray group but persisted for over 1 week in the placebo group.

CONCLUSION

Rebound congestion is objectively present in patients with perennial allergic rhinitis after 3 weeks of oxymetazoline spray. Rebound congestion is reduced by concomitant budesonide aqueous nasal spray use.

SIGNIFICANCE

This study supports the common clinical practice of nasal steroid sprays to ameliorate rebound congestion concomitant with and after cessation of topical decongestant sprays.

Eosinophilic mucin rhinosinusitis: a distinct clinicopathological entity

BACKGROUND

Allergic fungal sinusitis (AFS) was recognized in 1981. Since 1983, a form of sinusitis histologically similar to AFS except for the absence of fungal hyphae has also been noted. The designation "eosinophilic mucin rhinosinusitis (EMRS)" is proposed. Its relationship to AFS is controversial and problematic.

OBJECTIVE

To determine whether distinctive clinical and immunological differences exist to differentiate the histological entity of EMRS from AFS.

STUDY DESIGN

Literature review and comparison of cases of AFS (n = 418) to EMRS (n = 40) from the literature, as well as cases of AFS (n = 13) and EMRS (n = 29) accrued in the present study.

RESULTS

A total of 431 AFS patients were compared with 69 EMRS patients. The mean age of patients with AFS was significantly younger than patients with EMRS (30.7 y compared with 48.0 y, respectively; P < .001). Male-to-female ratios were 1.03:1 and 1.26:1 for AFS and EMRS, respectively, and were not significantly different. Forty-one percent of patients with AFS were asthmatic compared with 93% of patients with EMRS (P < .0001). Thirteen percent of patients with AFS were aspirin sensitive compared with 54% of patients with EMRS (P < .0001). Polyp occurrence was almost 100% in both groups. Eighty-four percent of patients with AFS had allergic rhinitis (AR), while only 63% of patients with EMRS had AR (P = .004). Fifty-five percent of AFS patients had bilateral disease, in contrast to the 100% of EMRS patients with bilateral disease (P < .0001). Although average total immunoglobulin E (IgE) was elevated in both groups, it was significantly more elevated in AFS patients (range, 12-13,084 mg/ dL; mean, 1,941 mg/dL) compared with EMRS patients (range, 14-1,162 mg/dL; mean, 267 mg/dL; P < .001). Total immunoglobulin G (IgG) and IgG subclasses were seldom reported in the cases available from the literature of either AFS or EMRS. However, in the present series of EMRS, IgG1 deficiency occurred in 50% of evaluated patients (mean, 475 +/- 175 mg/dL; range, 250-869 mg/dL; normal, 422 to 1,200 mg/dL) but in no cases of AFS reported in the literature.

CONCLUSIONS

Significant clinical and immunological differences exist to distinguish AFS from EMRS. It is postulated that AFS is an allergic response to fungi in predisposed individuals, while EMRS occurs because of a systemic dysregulation of immunological controls. Because EMRS is a systemic disease, unilateral disease is not seen. In contrast, AFS, an allergic response to fungi, may occur unilaterally or bilaterally depending on the antigenic stimulation. EMRS also has a significantly higher association with asthma, an increased incidence of aspirin sensitivity, and an increased incidence of IgG1 deficiency. Therapy with a systemic steroid, a potent and indiscriminant anti-inflammatory agent, is a useful adjunct in both disorders. Fungal immunotherapy following surgical extirpation of AFS is useful in preventing AFS recurrence. It is predicted that fungal immunotherapy and antifungal agents will be ineffective in patients with EMRS. It is important to differentiate these two similar histopathological entities in future trials assessing therapeutic efficacy. Inclusion of both entities in a study could obscure recognition of the true effectiveness of intervention, because of the possible variable response differences between the two entities. This study shows that significant clinical and immunological differences exist between EMRS and AFS. The future awaits an exploration of the pathophysiological basis of these differences.

Mucormycosis of the nose and paranasal sinuses

Rhinocerebral mucormycosis is an invasive fungal infection initiated in the paranasal sinuses that frequently progresses to orbital and brain involvement. If recognized early, involvement is limited to the nasal cavity and paranasal sinuses. Diabetics in poor control are at greatest risk, however, any immunocompromised individual may be infected. The mainstays of therapy are reversal of immunosuppression, systemic amphortericin B, and surgical débridement. Survival has improved dramatically, yet deaths still occur if the infection is not recognized and not treated early in its course or if the source of immunocompromise is not reversible. Several case examples illustrate the clinical course of this unusual, but potentially fatal, fungal infection. Taxonomy, clinical presentation, diagnosis, and management of mucormycosis of the paranasal sinuses are reviewed in detail.

Definitions of fungal rhinosinusitis

Classification of fungal rhinosinusitis is important for the accurate prediction of prognosis and direct therapy. The most important distinction is between invasive and noninvasive fungal rhinosinusitis. Within the invasive division are acute invasive and chronic invasive (granulomatous and nongranulomatous forms) rhinosinusitis. Within the noninvasive division are saprophytic colonization, fungus balls, and allergic fungal rhinosinusitis. This article briefly outlines the definition and management of each of these manifestations.

Geographic variation in allergic fungal rhinosinusitis

Allergic fungal rhinosinusitis (AFRS) has a worldwide distribution. This survey of 20 otolaryngologic practices throughout the United States confirmed a variation in the frequency of AFRS relative to endoscopic sinus procedures performed for all other diagnoses. The highest incidence occurred in Memphis, Tennessee at 23%, with three other southern practices reporting a frequency of at least 10%. In the northern locations the frequency ranged from 0 to 4%. No correlation with mould counts was demonstrated, possibly because of incomplete mould data relative to most of the surgical locations.

Fungus balls of the paranasal sinuses

Fungus balls of the paranasal sinuses represent a noninvasive manifestation of fungal sinusitis. Patients are immunocompetent but no more allergic than the general population. There is little tissue reaction to the tangled mat of hyphae. If the patient becomes immunocompromised, then the fungus ball may become invasive, as illustrated by an included case report. One hundred sixty-three additional cases of patients with paranasal sinus fungus balls are reviewed from the literature.

Quantitative analysis of microdebriders used in endoscopic sinus surgery

PURPOSE

To develop a standardized in vitro model for evaluating efficacy of the microdebriders and to assess whether differences in efficacy exist among available microdebriders. Microdebriders combine suction of tissue with amputation by a hollow rotating cutter. Several models are available, and they are increasingly popular in endoscopic sinus surgery.

MATERIALS AND METHODS

Seven microdebriders were tested by using a standardized soft tissue model (standard fresh raw oysters excluding muscle) and a firm tissue model (standard fresh raw oyster muscle). Efficacy was measured in grams of tissue aspirated per minute. Models to simulate lamina papyracea (eggshell) and dura (egg sac) were also tested with each microdebrider.

RESULTS

Statistically significant differences in soft tissue aspiration were found between most microdebriders ranging from the Xomed (Jacksonville, FL) Straight Shot/4.0-mm blade (147 g/min); the ESSential Shaver (Smith & Nephew, Memphis, TN)/4.0-mm blade (99 g/min), the Linvatec (Largo, FL)/4.2-mm blade and Dyonics (Burscheid, Germany)/3.5-mm blade and Wizard Plus/4.0-mm blade (range 43 to 46 g/min), followed by the Hummer II (Stryker, Santa Clara, CA) 4.0-mm blade (22.5 g/min), and finally the Xomed Wizard Plus/3.5-mm blade at 16 g/min. The Xomed Straight Shot/4.0 blade was statistically superior to all other microdebriders in efficiency of aspiration in the firm tissue model. All microdebriders were able to abrade a "bony" spicule and intact "dura," whereas none could abrade intact "bone."

CONCLUSIONS

Significant differences exist among the various microdebriders in this standardized model of efficiency of aspiration. Additional clinical factors including cost, safety, ease of use, and adaptability should also be considered in the choice of a microdebrider.

Allergic rhinitis and rhinosinusitis. Is there a connection between allergy and infection?

Each year allergic rhinitis and rhinosinusitis account for millions of office visits and billions of dollars spent on prescription and nonprescription drugs. Although the causes and symptoms of these two ailments differ, there is evidence that they are linked. The authors explain how effective control of allergy symptoms can reduce the incidence and severity of rhinosinusitis.

Laryngeal framework surgery for the management of aspiration

BACKGROUND

During the past decade, laryngeal framework surgery has become the treatment of choice for the management of adductor paralysis of the vocal fold. The primary impetus for the use of this technique has been on the rehabilitation of voice. The purpose of this study was to ascertain the effectiveness of laryngeal framework surgery, including medialization laryngoplasty with silicone (MLS), with or without arytenoid adduction (AA), on eliminating aspiration, improving diet, and aiding in the subsequent decannulation of individuals with glottic insufficiency secondary to vocal fold palsy.

METHODS

A retrospective chart review was performed on all patients initially seen with vocal cord paralysis who were treated with laryngeal framework surgery from June 1992 to April 1996. The study comprised 70 patients, including 31 women and 39 men, with a median age of 57 years. Clinical information was obtained regarding the etiology of the lesion, characteristics of the vocal cord deficit, history of aspiration, the presence of other neurologic deficits or concurrent pulmonary disease, treatment, and outcome. To determine the effectiveness of MLS, with or without AA, we assessed the final outcome regarding the presence and degree of aspiration, diet, history of aspiration pneumonia, and decannulation.

RESULTS

Seventy patients underwent 77 MLS (three bilateral, four revisions), and 21 AA. Decreased aspiration was obtained in 96% of our patients. Seventy-five percent of those patients who had required a tracheotomy were decannulated.

CONCLUSIONS

These results support the use of laryngeal framework surgery for the effective treatment of aspiration in selected patients initially seen with deficits of the glottic closure secondary to vocal fold paralysis or paresis.

Endoscopic sphenopalatine artery ligation is an effective method of treatment for posterior epistaxis

Transantral ligation of the internal maxillary artery is the most widely used surgical technique for control of intractable epistaxis. Although this technique is highly efficacious, significant complications may occur, including oroantral fistula, damage to the infraorbital nerve, and recurrent bleeding. An endoscopic transnasal approach for ligation of the terminal branch of the internal maxillary artery, the sphenopalatine artery, provides an alternative to transantral ligation. We have used endoscopic ligation of the sphenopalatine artery to treat 38 patients requiring surgical therapy for epistaxis. These cases were retrospectively reviewed to analyze the efficacy and morbidity of our technique. Five patients (13%) had significant recurrence of their epistaxis, of whom two required further surgical intervention. There were no major complications in this series. There were some minor sequelae including nasal crusting (34%) and paresthesia of the palate and nose (13%). The median hospital stay was 3 days (range 1 to 10). Endoscopic transnasal sphenopalatine artery ligation seems to be a safe and effective technique for management of posterior epistaxis.

Progressive septal and palatal perforation secondary to intranasal cocaine abuse

Septal perforation from intranasal cocaine abuse is well recognised. We present a case of progressive septal as well as palatal perforation. Progression from septal perforation to palatal perforation occurred after cessation of intranasal cocaine abuse. This patient had a weakly positive cytoplasmic antineutrophilic cytoplasmic antibody (C-ANCA) but no histologic evidence of Wegener's Granulomatosis. The differential diagnosis for septal and palatal perforation is reviewed. This case represents the fifth reported case of palatal perforation secondary to cocaine abuse in the literature, and the second associated with positive C-ANCA.

Cost-effective pharmacotherapy for allergic rhinitis

This article provides guidelines for pharmacotherapy to maximize symptom relief from allergic rhinitis. Consideration of frequency, severity, and site of symptoms is important in directing pharmacotherapy efficacy and maximizing cost-effectiveness. The agents available include antihistamines, decongestants, steroids, mast cell stabilizers, anticholinergic agents, and mucolytics. Appropriate indications for each and combinations of various agents are discussed within the context of drug efficacy, side effects, affordability, and ease of compliance. The direct and indirect costs of allergic rhinitis are not well delineated but are explored to put the costs of therapy in perspective.

Allergic rhinitis. Options for pharmacotherapy and immunotherapy

A trial of allergy medication can be both diagnostic and therapeutic in a patient with suspected allergic rhinitis, but with so many treatment options, it is sometimes difficult to know where to start. In this second of two articles on allergic rhinitis, Dr Ferguson provides information on efficacy and costs for various allergy drugs and discusses when to consider immunotherapy. The first article, beginning on page 110, discusses signs, symptoms, and triggering allergens.

Allergic rhinitis. Recognizing signs, symptoms, and triggering allergens

Runny noses, sneezing, nasal congestion, and other nuisance symptoms are part and parcel of primary care practice. But how can you quickly discern which symptoms are related to common colds and which stem from allergic rhinitis? Careful history taking usually provides clues, but allergy testing may be needed when triggers are not clear. In this first of two articles on allergic rhinitis, Dr Ferguson explains what to look for, what questions to ask, when to test for allergies, and how to modify a patient's environment to minimize problems. The second article, beginning on page 117, discusses pharmacologic treatment and immunotherapy for allergic rhinitis.

Primary extracranial meningioma of the maxillary antrum

A case of primary extracranial meningioma of the maxillary antrum is reported. A 45-year-old male presented with symptoms of chronic sinusitis. Imaging studies showed a soft tissue mass with calcification, filling the maxillary antrum. The mass was removed surgically, and pathological studies revealed a ribroblastic meningioma. The maxillary antrum is an uncommon location of primary extracranial meningioma, and our case is the sixth to be reported in that location.

Allergic fungal sinusitis: allergic, infectious, or both?

Allergic fungal sinusitis is a benign noninvasive sinus disease related to a hypersensitivity reaction to fungal antigens. A wide variety of fungal agents has been implicated, with the vast majority belonging to the Dematiaceae family. Allergic fungal sinusitis should be suspected in any atopic patient with refractory nasal polyps. Sinus computed tomograms and magnetic resonance imaging findings can be quite distinctive, but not diagnostic. Diagnosis requires histopathologic examination, which shows characteristic allergic mucin. Hyphae can be demonstrated on special fungal stains or confirmed by a positive fungal culture. At surgery, the diagnosis should be considered if thick, tenacious allergic mucin is encountered in the atopic patient with nasal polyps. Fungal cultures should then be obtained, and the pathologist alerted to the possible diagnosis of allergic fungal sinusitis. Current recommendations for therapy include conservative but complete exenteration of all allergic mucin. This can often be accomplished endoscopically. Adjunctive short-term systemic steroids are often helpful, and nasal steroid sprays should be continued long term. The length and dose of steroid therapy is controversial. Persistence of allergic fungal sinusitis with recurrence of sinonasal symptoms is common, particularly when there has been incomplete eradication of allergic fungal mucin. Even when the patient is clinically disease free, recurrence can occur, presumably from reexposure to fungal antigens. Therefore close clinical, endoscopic, and radiographic follow-up is important.

Acute and chronic sinusitis. How to ease symptoms and locate the cause

Patients with acute sinusitis often have purulent nasal discharge, facial pain, and congestion, whereas those with chronic sinusitis have more subtle signs. Infection, hyperreactivity reactions, anatomic obstruction, and underlying disease are among the causes and must be differentiated before appropriate care can be offered. Plain films and sinus transillumination may provide clues in adults but are of little value in young children. Computed tomography is much more sensitive but should be reserved for patients in whom maximal medical therapy has failed, who have a confusing presentation, or who are being considered for endoscopic surgery. Antibiotic therapy is still effective for bacterial infections, but penicillin-resistant organisms are on the increase. If there is no clinical improvement in 3 days, an agent with a broader spectrum of activity should be considered. A combination of agents and prolonged administration may be required for chronic sinusitis, and patients with recurrent symptoms may need endoscopic surgery. Such adjunctive agents as decongestants and saline or steroid nasal sprays may promote drainage. Antihistamines have no role in the treatment of sinusitis.

Leucocyte migration: effects of in vitro exposure to anaesthetic agents: possible potentiation of effects by adrenaline

The effect on in vitro migration of leucocytes and lymphocytes of various drugs used in anaesthesia have been determined in the concentration range 10(-2) to 10(-6) M. The drugs included, thiopentone, bupivacaine, lignocaine, adrenaline, noradrenaline, hydrocortisone, morphine (with and without preservative), lorazepam, suxamethonium, pancuronium and atropine. Toxicity and effect on random mobility after incubation for 1 and 18 h were also determined. Thiopentone depressed leucocyte function at a concentration of 10(-5) M which is comparable to clinical plasma concentrations. Increasing the duration of exposure of the cells to the drugs significantly lowered the concentrations at which depression of function was observed. At concentrations used during local infiltration in clinical practice, bupivacaine and lignocaine were toxic to both leucocytes and lymphocytes. Adrenaline, whilst having no direct effect on cell function, potentiated the effect of lignocaine. Morphine showed no effect at 10(-4) M, a level 1,000 times greater than the reported toxic plasma levels. However, this level falls within the range reported for drug addicts. No effects were found for the other drugs.

Serum transferrin receptor distinguishes the anemia of chronic disease from iron deficiency anemia

Recent studies have shown that the serum transferrin receptor is a sensitive, quantitative measure of tissue iron deficiency. This study was undertaken to determine the serum transferrin receptor's ability to distinguish iron-deficiency anemia from the anemia of chronic inflammation and to identify iron deficiency in patients with liver disease. The mean transferrin receptor level in 17 normal controls was 5.36 +/- 0.82 mg/L compared with 13.91 +/- 4.63 mg/L in 17 patients with iron-deficiency anemia (p less than 0.001). The mean serum receptor level was normal in all 20 patients with acute infection, including five with acute hepatitis, and was also normal in 8 of 10 anemic patients with chronic liver disease. Receptor levels were in the normal range in all but 4 of 41 patients with anemia of chronic disease. We conclude that unlike serum ferritin levels, which are disproportionately elevated in relation to iron stores in patients with inflammation or liver disease, the serum transferrin receptor level is not affected by these disorders and is therefore a reliable laboratory index of iron deficiency anemia.

Lectin-stimulated lymphocyte responses: use and misuse in clinical research

The use of mitogen stimulation assays in clinical research has increased rapidly during the last 25 years. However, little is understood about the mechanisms of action of mitogens. This, coupled with the complexity of the mitogen stimulation assay, has led to much misuse and abuse of this assay system. Data are presented that demonstrate the inherent variability of the assay system due to diurnal variation in the response of human lymphocytes to mitogen stimulation and to the variation in response between patients. It is argued that the use of the assay should be confined to rigorously controlled studies using either animal lymphocytes or paired samples from humans, one of which should be treated in vitro with test material.

Adjunctive hyperbaric oxygen for treatment of rhinocerebral mucormycosis

The therapy of rhinocerebral mucormycosis includes aggressive surgical debridement, administration of high-dose amphotericin B, and control of underlying predisposing conditions, especially diabetes and immunosuppression or immunodeficiency. Hyperbaric oxygen suppresses fungal growth in vitro and has theoretical value in treating mucormycosis because it reduces the tissue hypoxia and acidosis that accompany vascular invasion by the fungus. In a retrospective review of patients at Duke University Medical Center with rhinocerebral mucormycosis, six patients were treated with hyperbaric oxygen and seven cases (involving six patients) were treated without hyperbaric oxygen. All patients received surgical debridement and amphotericin B. Two of six patients receiving hyperbaric oxygen therapy died, and four of seven patients not receiving hyperbaric oxygen therapy died. Adverse effects from hyperbaric oxygen were minimal. Because mucormycosis occurs infrequently, this retrospective review involved a small number of patients. Despite this limitation, adjunctive hyperbaric oxygen appears to be a promising clinical modality for the treatment of rhinocerebral mucormycosis and warrants further investigation.