Jack Thrasher, PhD, is extremely knowledgeable on the topic of mold and how it impacts your health. Interestingly, from a toxicity point of view, some mycotoxins that molds produce are actually far more toxic than heavy metals, in terms of concentration. Mold mycotoxins also tend to affect more biological systems in your body than pesticides or heavy metals do.

"For example, stachybotrys produces mycotoxins referred to as trichothecene. They inhibit protein synthesis. It infects every organ of your body from your toes to the top of your head," Dr. Thrasher says. "I really think that the molds are much more dangerous from that point of view."

This flies in the face of what is commonly appreciated about toxic contaminants. Most would assume that pesticides or heavy metals would be far more dangerous. However, mold is a very significant health issue. And despite the fact that molds have been around forever, mankind has not developed greater tolerance against them than more modern chemical toxins. Part of that is because they tend to rapidly mutate.

"Let's take a look at Cryptococcus for example," Dr. Thrasher says. "Cryptococcus used to be endemic to the desserts of southwest United States. Now there is a new species… that was accidentally released up in Vancouver, Canada. It's spreading from the northwest throughout the country. It's a mutated form, [and] highly pathogenic to humans. About 25 to 30 percent of the humans who have become infected with it die… When they mutate they avoid our immune system.

The other thing they can do is produce chemicals that suppress your immune system at the same time. So therefore, I don't think we'll ever become resistant to these organisms."

Mold—A Hidden Pandemic in America?

According to Dr. Thrasher, the prevalence of mold in America is so great, he refers to it as pandemic. As many as 40 percent of all American schools and at least 25 percent or more of all homes are believed to be affected by mold and microbial growth due to water intrusion. A large portion of the problem stems from shoddy construction.

He explains:

"One thing that I have seen and observed by working with individuals in the field who understand construction, is that construction is extremely poor in the homes we have today. Plus, they're using building materials that are tremendous good food material for the microbes.

When I was a child… all the homes were built with genuine lath and plaster on the inside. [Now] you walk in and knock on any wall and you have what we call wallboard. That wallboard loves and is a good growth medium for all forms of mold. Everyone that I can think of, almost everyone now has carpets. The backside of carpets is also a great growth medium for mold and bacteria.

… The other type of home that I'm seeing that is of tremendous potential problems to the homeowner is homes that are built with a basement… [T]hey put the concrete down, and there is no water barrier between the earth and the concrete wall of the basement.

The same thing with the foundation, there is no water barrier. So when you water your yard, when there are heavy rains and things like this, the moisture… goes right to the foundation and into the basement or underneath the house, and then the moisture wicks up through the home, increasing humidity.

All of that increasing humidity, anything above 60 percent is going to lead to growth of mold and bacteria… People have to be very careful about this situation. That's the reason why I call it a pandemic."

Gutters can also cause problems. You need to be mindful of the drainage from your roof. I didn't realize this myself, and suffered the consequences when one of the gutters on my home drained onto the ground directly beside the wall, and the water seeped straight through to my basement. So you want to make sure the downspout is far enough away from the building. Ideally, it should empty at least 5 to 10 feet from the wall.

You also want to take care that the soil next to the walls of your home slopes away from the walls, to prevent water from collecting around the foundation. And make sure your lawn sprinklers do not spray the walls. Other common construction issues that can contribute to water intrusion and subsequent mold proliferation include:

• Using polyethylene PVC piping instead of copper or galvanized piping, which can be easily punctured by nails or staples
• Bath tubs installed with improper sealing around the drain
• Improperly sealed sinks and garbage disposal
• Installing particleboard (waferboard) after it has been rained on during construction

Bacteria—Another Health Risk Related to Mold Damage

Growing right along with mold are what's called 'gram negative' and 'gram positive' bacteria. Just like mold, they require moisture and organic material to thrive, and the synergistic action between mold and bacteria further increase and worsen inflammatory health conditions.

"The gram positive are group of bacteria that are being totally overlooked," Dr. Thrasher says.

"These positive bacteria consist of several bacilli, cocci, and one group called the actinomycetes. The actinomycetes contain several different groups of bacteria like mycobacterium. We're all familiar with… mycobacterium tuberculosis.

There are 139 other species of mycobacterium that can grow in our environment and 11 to 12 of those in the indoor environment are very serious human pathogens and can cause a condition called mycobacterium avium complex... and this is a very dangerous situation. It causes serious infection of the lungs and can spread throughout the body. Many of the symptoms are those of hypersensitivity pneumonitis. The condition can go on and develop into an asthma-like condition and then also into sarcoidosis particularly of the mediastinum.

Then the other group are the streptomyces… Streptomyces gave rise to a lot of antibiotics. Also, streptomyces are a source of many of the chemotherapeutic agents that are used today. These organisms are growing in the indoor environment."

Gram negative bacteria are also extremely harmful. When they die, they release their cell walls, which are referred to as lipopolysaccharide, or endotoxins. These endotoxins can severely exacerbate asthma and other conditions because they are highly inflammatory. According to Dr. Thrasher, research indicates the inflammation they cause can also affect your brain and other organs.

How to Detect a Mold Problem

Clearly, the first step would be to conduct a visual inspection. A musty, mildew odor is a tip-off that you need to check the area in question for any visible signs of mold. If you can't see any visible traces of mold, Dr. Thrasher recommends taking an air sample, and using a moisture meter to determine the moisture level in the area.

"I use a moisture meter on every wall of the building or the home looking for hidden moisture. The moisture content of wood flooring, for example, should be no more than 10 to 12 percent. I'm finding floors that have moisture content of 48 percent. Exterior walls shouldn't have anything more than 15 percent, and I'm finding exterior walls with 40, 50, 60 percent.

… The other thing I recommend is to not rely on air samples from mold spore counts. Invariably, that will give you misinformation. The number of mold spores that are in the indoor environment and the outdoor environment vary over the day; it's a diurnal type variation… So it's not a very reliable test for what's in the air.

Secondly, there are certain bacteria that do not release their spores into the air very regularly and you won't find them in the air… So become educated as to what to look for and how to look for it, and don't accept somebody coming in, taking an air sample and saying, "There is nothing wrong with this because the indoor counts are less than outdoor counts." That's wrong logic. Certain species of mold grow indoors much more regularly than they do outdoors. So you have to look at the species of mold, not just the spores."

A better option is to do 24-hour monitoring. However, this type of testing cannot be performed by a typical mold inspector. You need to hire a high-level mold expert for this type of air testing. (I'll list several sources for finding a qualified expert below.) Dr. Thrasher also suggests interviewing the expert in question to find out who they typically work for.

"If they're doing work for insurance companies stay away from them," he says. "You want somebody who is unbiased… [Also] ask them the question, "If you take the airborne mold in the indoor environment can it hurt you or cause toxic reaction?" If the person says, "No, don't worry about it. All it can do is cause allergies," then stay away from that person. That person is not well informed."

After air sampling, Dr. Thrasher also takes swab and bulk samples of the mold growth; actually cutting out a piece of the affected area if necessary, for proper lab testing. Dr. Thrasher explains what he typically tests for:

"We culture for the bacteria. We culture for the mold. We do what we call ERMI (Environmental Relative Moldiness Index), which is an EPA test that was developed by a group in the EPA. This is a PCR-DNA analysis for 31 different species of mold… that is very inexpensive, relatively speaking. It costs $350 to do that test… [W]e take swab samples looking for endotoxins. We also look for… polysaccharides called 1,3-beta-D-glucans… We want to get a good idea what's going on in the indoor environment."

Next Step: Remediation

As soon as you've identified the problem, you have to stop the water intrusion and remediate the problem at its source.

"Let's say you have an infested wall that's in the middle of the home between the living room and say, the adjoining den; what is recommended is that the whole area must be walled off from the rest of the house… In other words, you drape them with a plastic and you have to tie the plastic down with masking tape so that that area will not, theoretically, contaminate the rest of the house," Dr. Thrasher explains.

While you can clean affected metal objects, all organic materials (such as wood, particle board, and carpets) must be completely removed and replaced. You want to make sure that the contractor you hire for the job uses a HEPA (High Efficiency Particulate Arresting) filtration machine to trap minute particles, and that they're meticulous when using it.

WARNING!! Be Careful How You Chose Your Remediator

There is no question that a high quality active air purifier can help control mold issues but it will NOT remediate against them. You can use the best air filters and purifiers and they will never solve the problem if you continue to have water intrusion into you home that increases the humidity and feeds the growth of the mold.

You will need to stop the water at its source and carefully remove and clean the mold infested materials. While this may superficially seem an easy task, let me assure you that it isn't.

I recently had a leak in my basement that was improperly remediated for $10K. The cause was not addressed so the problem worsened, which more than tripled the price to properly clean it up. That is part of the reason that prompted me to contact some of the leading experts in this area and learn how to do this properly.

So let me tell you from personal experience, you need to find a qualified expert and professional that is certified by one of the agencies below. I would also suggest getting several bids for the work. You can find contractor or professional listings on the following sites. Both the IICRC and NORMI are certifying organizations for mold remediation, but the IICRC certification is perhaps the most widely used:

• IICRC (Institute of Inspection, Cleaning and Restoration Certification)
• ACAC (American Council for Accredited Certification)—a certifying body that is third-party accredited.
• The IAQA (Indoor Air Quality Association)—a membership organization with no certification program (the ACAC handles this by agreement)
• RIA (Restoration Industry Association)
• NORMI (National Organization of Remediators and Mold Inspectors) 

Keep in mind that a mere certification or listing may not be enough. Also evaluate the remediator's qualifications and insurance (liability as well as workman's comp). With the ACAC, there are a few different levels.

How to Clean Up Minor Surface Mold

If you have just a small area of surface mold, you probably don't have to call in an expert. However, only attempt to clean it if it's limited to the surface of a small area. You cannot "clean" deep-rooted mold. Dr. Thrasher has one word for those of you who have bought into the home-remedy advice to "kill off mold" with ammonia or bleach: Don't.

"What happens is you'll kill the mold but you'll leave the carcass behind," Dr. Thrasher explains. "The carcass will disintegrate and release toxins into the air. So you really went from one problem (mold growth) to another problem; dead mold and the release of all of their toxins… and then once water is reintroduced in the environment, the mold will grow right back to the surface."

However, for minor visible surface mold on say a baseboard, or on a piece of furniture, you could use a little bit of sodium bicarbonate (baking soda) and vinegar to wipe it off.

"I just use the concentrated vinegar and baking soda," he says. "All you need is a couple of tablespoons [of baking soda] to a quart of water. The vinegar I just take straight out of the bottle… I generally do the vinegar first and then follow it with the baking soda… The vinegar will kill the mold and the bacteria but you're going to leave residue on the surface and so you scrub the surface to try to get rid of the residue.

… I never validated that procedure, but that's what I recommend; what I do use and it seems to work, but I haven't validated it with research data. I have to be honest with the population out there."

What about Ozone Generators?

While Dr. Thrasher does not recommend using an ozone generator, other indoor air experts do. Ozone generators essentially generate photocatalytic oxidation that can help destroy airborne mold. However, Dr. Thrasher strongly cautions against their use, stating that oxidizing an organic chemical of any kind will create free radicals, and he also points out that ozone can be highly irritating to your mucous membranes and lungs.

Personally, I believe the claim that ozone generators facilitate the removal of volatile organics is correct… But do beware that they should not be used when you're in the room at levels higher than the EPA recommends, and they do pose a danger to both plants and pets. However, the ozone dissipates quickly, so after airing the area out for about 20 minutes, it's safe to return.

Keep in mind that this is different from air filtration, as the ozone generator actually purifies the air and neutralizes any odors at the source, on the molecular level.

Could Your Health Problems be Related to Mold?

Common health problems that can be attributed to poor and potentially toxic indoor air quality include:

If you have any of these issues, it may be worthwhile to consider your indoor air quality, and the possibility that your health problems may be related to mold. A meta-analysis, published in last year in the journal Environmental Health, concluded that:

"Residential dampness and mold are associated with substantial and statistically significant increases in both respiratory infections and bronchitis. If these associations were confirmed as causal, effective control of dampness and mold in buildings would prevent a substantial proportion of respiratory infections."

It's important to determine whether or not your health problems are indeed due to mold, in order to properly treat it. Most doctors will simply prescribe an antibiotic for chronic sinusitis, for example. But if your sinusitis stems from bacteria- and mold growth in your home, it's not going to clear up. The next step is typically to prescribe either prednisone or a corticosteroid, which could further worsen your condition.

"You want to stay away from the corticosteroids; you want to stay away from the antibiotics," Dr. Thrasher warns. "What you need to do is to do a culture. Go to a good ENT physician and actually get a diagnosis of what is going on inside of your sinuses. You want to stay away from the corticosteroids because two weeks use -- or even less than this -- of corticosteroids will increase your risk of other infections. Corticosteroids inhibit the oxidative burst produced by macrophages… Let's say you have mold that's growing in your sinuses. So the macrophages in your body, called the innate immune system, are in there gobbling up the spores of the mold, correct?

Then what happens is they put you on corticosteroids, and the role of the macrophages, they'll gobble them up, engulf them, and then produce oxidative burst that kill the spores and the bacteria. The corticosteroids do not inhibit the engulfing aspect of it so they take up the spores and the bacteria, but the corticosteroids inhibit the extra oxidative burst produced by the macrophages. Now, the macrophages contain live spores and bacteria. Now where do they go?

They go any place else in the body they want to go to. So therefore you have increased your risk of other infections particularly fungal infections. I've seen individuals who have been put on corticosteroids because they have been exposed to these indoor environments and then, sometime down the road, have been diagnosed with Aspergillosis."

That's definitely a concern. Additionally, long term use of steroids has other side effects that are well documented, including increasing your risk of osteoporosis and cataracts, and disrupting your hormone balance. So, educate yourself on indoor air quality, and particularly on mold.

Results. The mean age of patients was 38.8 years; 65% were male. The prevalence and overall mortality were 36% and 44%, respectively, for diabetes; 19% and 35%, respectively, for no underlying condition; and 17% and 66%, respectively, for malignancy. The most common types of infection were sinus (39%), pulmonary (24%), and cutaneous (19%). Dissemination developed in 23% of cases. Mortality varied with the site of infection: 96% of patients with disseminated disease died, 85% with gastrointestinal infection died, and 76% with pulmonary infection died. The majority of patients with malignancy (92 [60%] of 154) had pulmonary disease, whereas the majority of patients with diabetes (222 [66%] of 337) had sinus disease. Rhinocerebral disease was seen more frequently in patients with diabetes (145 [33%] of 337), compared with patients with malignancy (6 [4%] of 154). Hematogenous dissemination to skin was rare; however, 78 (44%) of 176 cutaneous infections were complicated by deep extension or dissemination. Survival was 3% (8 of 241 patients) for cases that were not treated, 61% (324 of 532) for cases treated with amphotericin B deoxycholate, 57% (51 of 90) for cases treated with surgery alone, and 70% (328 of 470) for cases treated with antifungal therapy and surgery. By multivariate analysis, infection due to Cunninghamella species and disseminated disease were independently associated with increased rates of death (odds ratios, 2.78 and 11.2, respectively).

Conclusions. Outcome from zygomycosis varies as a function of the underlying condition, site of infection, and use of antifungal therapy.

Zygomycosis has emerged as an increasingly important pathogen during the past decade [1–5]. This increase has been particularly evident in hematopoietic stem cell transplant recipients and patients with hematological malignancies [6–12]. Unlike other filamentous fungi that are largely opportunistic in patients with cancer, transplant recipients, and patients with inherited immunodeficiencies, zygomycosis also can be a frequently lethal infection in hosts with greater immunocompetency, such as those with diabetes mellitus [13–23], those receiving deferoxamine therapy [24–32], injection drug users (IDUs) [33–39], and those with no apparent immune impairment [40–46].

To date, there has been no definitive, comprehensive review of the literature on zygomycosis to guide our understanding of the epidemiology and outcome of zygomycosis in the general population. We therefore reviewed the English-language literature for all cases of zygomycosis, from the original case report in 1885 to the present. In this review, we sought to understand the distribution of infection within the general population and to ascertain whether the patterns of infection are associated with specific host factors and outcomes.

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Results

The first case of zygomycosis reported in the literature was by Paultauf in 1885 [48]. This case, however, did not meet the predefined eligibility criteria and, consequently, was not included in our database. The first case to be included was reported in 1940. A total of 1049 individual cases of zygomycosis from 1940 through 2003 were identified. Of these, 120 cases were excluded from the database because they did not meet the stringent predefined inclusion criteria. The total database thus consisted of 929 cases (in 1 patient each) reported in 459 published reports [14–476].

Demographic characteristics. The underlying conditions and their associated all cause mortality are summarized in table 1. The mean age was 38.8 years, and the median age was 40.0 years (range, 0.005–80 years). A total of 65% of all Zygomycetes infections occurred in males. The overall mortality in the total population was 54% (504 of 929 patients).

Diabetes was the most common underlying condition. Only 68 patients (20%) with diabetes had type I diabetes, and of these, 33 (48%) had documented ketoacidosis. Conversely, most patients with diabetes in this review had type II diabetes (n = 187), with 64 (34%) having documented ketoacidosis. In 54 (16%) of 337 patients with diabetes, zygomycosis presented as the diabetes-defining illness. The second largest patient population consisted of persons who had no primary underlying disease at the time of infection. Among 154 patients with malignancy, 147 (95%) had a hematological malignancy. There were only 7 cases of zygomycosis reported in patients with a nonhematological malignancy.

Secular trends in reported hosts. There was an increase in the reporting of zygomycosis in all underlying host populations during the study period ( figure 1 ). Diabetes was the most commonly reported underlying condition in each decade. However, an increasing proportion of other host populations, including those with malignancy, recipients of bone marrow transplants, recipients of deferoxamine, IDUs, and patients with no underlying condition becomes apparent in the 1980s and 1990s.

Sites and patterns of infection. The primary site of infection at the time of initial diagnosis varied as a function of the host population (figure 2). Sinus involvement consisting of rhinocerebral, sinus, and sino-orbital infections constituted the majority of infections (222 [66%] of 337) in patients with diabetes. This differs from the pattern of infection in persons with no underlying condition, in which cutaneous zygomycosis constituted one-half of all cases. By further comparison, pulmonary zygomycosis constituted more than one-half of all sites of infection in patients with malignancy and recipients of bone marrow transplants. Sinus involvement was the second most common pattern of infection in this patient population. Patients undergoing solid organ transplantation had another distinctive pattern, with relatively similar frequencies of pulmonary and sinus infections. On the other hand, patients receiving deferoxamine therapy presented more frequently with generalized disseminated zygomycosis, compared with other host categories. Finally, cerebral zygomycosis was the most common presenting pattern of infection in IDUs. The pattern of cerebral zygomycosis in IDUs was hematogenous and was seldom associated with rhinocerebral infection.

fig 2

Patterns of zygomycosis, by host population

The patterns of infection and their associated all-cause mortality are detailed in table 2. The paranasal sinuses were the most common site of infection, presenting in 39% of cases. Rhinocerebral infection was the most commonly reported pattern of sinus zygomycosis. Independent predictors for sinus zygomycosis were diabetes type 1 (OR, 4.04; 95% CI, 2.36–6.90), diabetes type 2 (OR, 6.35; 95% CI, 3.89–10.36), and injection drug use (OR, 0.15; 95% CI, 0.04–0.51). Pulmonary disease was the second most common presenting pattern. Approximately one-half of all cases were restricted to the lung, whereas the remaining cases were either disseminated or complicated by deep extension into the chest wall, pulmonary artery, or heart. Independent risk factors for pulmonary zygomycosis were infection with Cunninghamella species (compared with infection with Rhizopus species) (OR, 7.75; 95% CI, 2.44–24.58), neutropenia (OR, 2.28; 95% CI, 1.26–4.11), and receipt of a solid organ transplant (OR, 3.41; 95% CI, 1.41–8.20).

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Figure 3

Percentages of zygomycosis cases documented by culture since the 1940s, by decade

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Figure 4

Mortality due to zygomycosis since the 1940s, by decade

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Figure 5

Median duration of polyene therapy for patients with zygomycosis who survived or who died, by host population

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Table 1

Demographic and clinical characteristics of 929 patients with zygomycosis, 504 of whom died.

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Table 2

Infection patterns among 929 patients with zygomycosis, 504 of whom died.

Cutaneous involvement was the presenting pattern in 176 (19%) of 929 patients. Penetrating trauma was reported for 60 (34%) of these patients, dressings were reported for 26 (15%), surgery was reported for 26 (15%), burns were reported for 11 (6%), motor vehicle accident was reported for 5 (3%), and falls were reported for 5 (3%). The histories for the remaining 42 patients (24%) were not well described. Most cases were localized to the integument. However, deep extension to bone, tendon, or muscle occurred in 42 (24%) of 176 cases, and hematogenous dissemination from skin to other noncontiguous organs occurred in 35 (20%). Hematogenous dissemination from other organs to skin occurred rarely, in only 6 cases (3%). The majority of patients with cutaneous infection were either nonneutropenic or had no underlying condition. Independent risk factors for localized cutaneous infection were female sex (OR, 2.27; 95% CI, 1.46–3.55), no underlying condition (OR, 2.60; 95% CI, 1.32–5.14), prior surgery (OR, 5.40; 95% CI, 1.84–15.86), and HIV infection (OR, 2.62; 95% CI, 1.01–6.79).

There were 283 patients with CNS infection, of which 69% had rhinocerebral infection, 16% had localized cerebral infection, and 15% had hematogenous dissemination of infection from other organs to the brain. Both rhinocerebral infection and localized cerebral infection were associated with a mortality of 62%. Of patients with localized cerebral infection, most were IDUs who were independently associated with the development of primary CNS disease (OR, 80.25; 95% CI, 26.69–241.28). There were no patients with diabetes who had hematogenous dissemination to the brain. Instead, all CNS infections in patients with diabetes occurred in those with rhinocerebral infection.

Gastrointestinal infection occurred in 65 patients (7%). The rate of dissemination to other noncontiguous organs was 38% (25 of 65 patients). Mortality was high, primarily because of bowel perforation. The infection occurred predominantly in low birth weight infants, patients with diarrhea and malnutrition, and patients receiving peritoneal dialysis.

The risk for development of disseminated zygomycosis from any site varied as a function of host characteristics. Independent risk predictors were burns (OR, 6.26; 95% CI, 1.16–33.81), prematurity (OR, 2.85; 95% CI, 1.26–6.43), deferoxamine use (OR, 2.76; 95% CI, 1.66–4.59), diabetes (OR, 0.29; 95% CI, 0.17–0.50), no underlying condition (OR, 0.47; 95% CI, 0.25–0.91), and HIV infection (OR, 0.15; 95% CI, 0.03–0.63).

Microbiologic and histopathologic findings. All patients had infection documented either histologically or by culture. A positive culture result was obtained in 50% of cases (table 3). There was a clear increase in culture positivity over time, with 71% of all cases since 2000 diagnosed on the basis of culture results (figure 3). Among the 465 cases with a culture positive for a Zygomycetes organism, Rhizopus species were the most commonly recovered organisms, with Rhizopus oryzae the most frequently recovered species.

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Table 3

Microbiological findings for 465 patients with zygomycosis, 219 of whom died.

Sex and zygomycosis. Zygomycosis occurred primarily in males (605 [65%] of 929 cases). The following genera were clearly associated with infection in males, constituting >78% of infections in this group: Basidiobolus, Cunninghamella, Absidia, and Apophysomyces (table 4).

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Table 4

Relationship between microbiologic findings and male sex in 465 cases of culture-confirmed zygomycosis.

Entomophthorales organisms caused 7.2% of all zygomycoses in this review. The order Entomophthorales differed from the order Mucorales in overall survival (69% vs. 52%) and in the frequency of persons with no underlying condition (69% vs. 50%). Of infections due to Conidiobolus species, 5 (50%) of 10 were cutaneous. Of infections due to Basidiobolus species, 7 (78%) of 9 were gastrointestinal.

Treatment. Of the 929 cases reviewed, 596 (64%) were treated with some form of antifungal chemotherapy (table 5). Survival in this group was 62% (369 of 596 patients). Of these 596 patients, 532 (89%) received amphotericin B deoxycholate, with an overall survival of 61%. Survival was 57% (51 of 90 patients) for those treated with surgery alone; survival increased to 70% (328 of 470 patients) for those treated with a combination of surgery and antifungal chemotherapy. A total of 241 patients (26%) received no treatment for their infection. Within this subgroup, the survival rate was 3% (8 of 241 patients).

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Table 5

Treatment administered to 929 patients with zygomycosis, 425 of whom survived.

Outcome. Analysis of survival by decade revealed that overall mortality improved from 84% in the 1950s to 47% in the 1990s (figure 4). However, mortality due to zygomycosis has remained essentially unchanged since the 1960s, when amphotericin B deoxycholate was widely introduced (figure 5).

Table 6 summarizes results of the multivariate regression analysis of risk factors for mortality among all patients. Significant risk factors for mortality included disseminated disease, renal failure, and infection with Cunninghamella species. Conversely, type I diabetes and no underlying condition were independently associated with a reduced risk of death. Compared with no receipt of antifungal therapy, all forms of antifungal therapy were also significantly associated with a reduced risk of mortality. Patients who underwent surgery as primary therapy were also significantly more likely to survive. Pulmonary, rhinocerebral, kidney, and gastrointestinal infection were associated with the highest risks of mortality.

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Table 6

Multivariate model of risk factors for mortality among patients with zygomycosis.

• Received January 27, 2005.
• Revision received April 18, 2005.

• © 2005 by the Infectious Diseases Society of America