Sign in to see reasons why you may or may not like this based on your games, friends, and curators you follow. Sign In or Open in Steam. MAC infection is a serious condition that can cause damage to the lungs. MAC infection is not contagious. Common signs and symptoms of MAC lung disease include fatigue, chronic cough, shortness of breath, night sweats, coughing up blood and weight loss. Symptoms may persist or worsen despite being treated for another lung condition. Mast cell activation syndrome can cause temporary symptoms in multiple organ systems. Learn more about its common triggers and available treatment options. Ensure that your operating system is Windows 8 or higher for personal computers or Mac OS X 10.8 or higher. Use a minimum screen resolution of 1024 x 768. Have a broadband internet connection with download speed of 3 megabits per second (Mbps) or greater.
Pulmonary Mycobacterium avium complex (MAC) infection is a type of non-tuberculous mycobacterial (NTM) infection. It is relatively common and continues to pose significant therapeutic challenges. In addition, the role of MAC in pulmonary pathology remains controversial in many instances.
Epidemiology
MAC infections often occur in patients with a pre-existing pulmonary disease or those with depressed immunity. However, it is also seen frequently in otherwise healthy patients, with a predilection for older women who deliberately suppress the cough reflex (Lady Windermere syndrome) 1-3.
Associations
A number of patient groups have been associated with increased risk of pulmonary MAC. They include 2,3:
- elderly, white, thin women: nodular bronchiectatic form (see below)
- middle-aged or elderly males who are smokers (often with COPD) or alcoholics: upper lobe cavitary form (see below)
- immunocompromised patients, e.g. AIDS
- patients with cystic fibrosis: MAC isolated in up to 13% of patients
- patients with alpha-1-antitrypsin deficiency
- other causes of bronchiectasis
- chronic obstructive pulmonary disease (COPD)
Isolation of MAC from a patient's lung is not pathognomonic of infection, as colonization is common, and thus microbiology needs to be correlated with clinical and radiographic appearances 2,3.
Clinical presentation
Pulmonary MAC infection is typically insidious, with a chronic cough usually productive of purulent sputum being most common. Hemoptysis and constitutional symptoms are not typical 2.
Pathology
Mycobacterium avium and Mycobacterium intracellulare are now considered together, and referred to as Mycobacterium avium complex (MAC) or Mycobacterium avium-intracellulare complex (MAIC). They cannot be distinguished on the grounds of human pathologic manifestation or imaging features, and are treated similarly, although M. avium has a predilection for chickens whereas M. intracellulare prefers rabbits 2,3.
They are ubiquitous organisms, found in both fresh and salt water, but do not tend to cause human disease. Patients with MAC infection, unlike those with pulmonary tuberculosis, are not contagious 2.
Variants
- hot tub lung: granulomatous pneumonitis from exposure to aerosolized Mycobacterium avium complex (MAC) organisms in contaminated water (may not necessarily imply infection) 4
Radiographic features
Three main forms of pulmonary MAC infections are recognized 3,5,6:
- upper lobe fibrocavitary pattern/cavitary form (classic infection)
- nodular bronchiectatic form/bronchiectatic form (non-classic infection)
- mixed form
In upper lobe cavitary form, thin-walled cavities with overall volume loss and fibrosis are the dominant feature, often also with features of endobronchial spread with tree-in-bud opacities seen elsewhere.
In the nodular or non-classic manifestation, the dominant feature is bronchiectasis with associated centrilobular nodules. Unlike pulmonary tuberculosis, there is no predilection for the upper lobes. In elderly white females, the right middle lobe and lingula are particularly affected.
See Full List On Radiopaedia.org
Plain radiograph
Bronchiectasis, seen as tram-track opacities and ring shadows, may be evident. Patchy airspace opacities are also common. Pleural effusions are uncommon 2. Upper zone cavities may also be seen with associated volume loss and scarring 3.
CT
The most common findings of MAC infections include 1,2: The art of shattering mac os.
- bronchiectasis and bronchial wall thickening: most common findings
- small centrilobular nodules and tree-in-bud appearance
- patchy consolidation
- a predilection for the right middle lobe and lingula is seen particularly in elderly white women
- pleural thickening may be seen, usually adjacent to parenchymal change
- upper lobe cavitation may also be seen, although it is more characteristic of pulmonary tuberculosis
Treatment and prognosis
Many treatment regimes have been published, with no clear gold-standard evident, although as is the case with pulmonary TB, multi-drug therapy is ideal to avoid resistance 2.
In patients who are unable to tolerate medical management, and who have an adequate respiratory reserve, resection of affected portions of the lung may be undertaken. Complications of surgery include bronchopleural fistulas, hemoptysis and empyema2.
In patients in whom isolates of MAC are not clearly pathogenic, follow-up is required, keeping in mind that evidence of radiographic progression may take a number of years to be convincing 3.
Prognosis depends on the form of the disease. In the upper lobe cavitary form, lung destruction is usually progressive and can lead to respiratory failure and death if successful treatment is not instituted.
In patients with the nodular bronchiectatic form (Lady Windermere syndrome) the disease is much more indolent, however, eventually, this form may also lead to enough parenchymal damage to result in respiratory failure and death 3.
Differential diagnosis
- Mycobacterium tuberculosis pulmonary infection:
- bronchiectasis is less commonly the dominant feature 1
- changes usually in the upper lobes 1
- see other causes of bronchiectasis
The underlying pulmonary abnormality (e.g. COPD, pneumoconiosis) may dominate the radiographic appearance.
- 1. Primack SL, Logan PM, Hartman TE et-al. Pulmonary tuberculosis and Mycobacterium avium-intracellulare: a comparison of CT findings. Radiology. 1995;194 (2): 413-7. Radiology (abstract) - Pubmed citation
- 2. Field SK, Fisher D, Cowie RL. Mycobacterium avium complex pulmonary disease in patients without HIV infection. Chest. 2004;126 (2): 566-81. doi:10.1378/chest.126.2.566 - Pubmed citation
- 3. Müller NL, Franquet T, Lee KS et-al. Imaging of pulmonary infections. Lippincott Williams & Wilkins. (2007) ISBN:078177232X. Read it at Google Books - Find it at Amazon
- 4. Hartman TE, Jensen E, Tazelaar HD et-al. CT findings of granulomatous pneumonitis secondary to Mycobacterium avium-intracellulare inhalation: 'hot tub lung'. AJR Am J Roentgenol. 2007;188 (4): 1050-3. doi:10.2214/AJR.06.0546 - Pubmed citation
- 5. Kim TS, Koh WJ, Han J et-al. Hypothesis on the evolution of cavitary lesions in nontuberculous mycobacterial pulmonary infection: thin-section CT and histopathologic correlation. AJR Am J Roentgenol. 2005;184 (4): 1247-52. doi:10.2214/ajr.184.4.01841247 - Pubmed citation
- 6. Martinez S, McAdams HP, Batchu CS. The many faces of pulmonary nontuberculous mycobacterial infection. AJR Am J Roentgenol. 2007;189 (1): 177-86. doi:10.2214/AJR.07.2074 - Pubmed citation
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With any company that's been around for more than 30 years—and with as many interesting, creative, and varied ideas Apple has had—there are bound to be a few Apple products that have slipped through history's cracks. New free slot machines. Along with its incredible successes, Apple has made its rightful share of clunkers and obscure products that quickly sunk to the bottom of the deep and vast ocean of public memory.
Come with us now as we explore these depths and dredge up five Apple products that probably won't get the blowout anniversary treatment on the virtual pages of Macworld.com
QuickTake 100
Apple Computer—known for its groundbreaking work with PCs, PDAs, and…digital cameras? Indeed, 1994 saw the release of Apple's QuickTake 100, one of the first consumer digital cameras in the US. The inaugural model of the QuickTake series debuted with an awkward form factor that resembled a one-eyed pair of futuristic binoculars. House of fun money.
Capable of storing eight photos at 640-by-480 resolution (or 32 at 320-by-240) on a whopping 1MB of internal flash memory, it was obviously primitive by today's standards. Apple released more powerful members of the QuickTake family over the next few years, but under the weight of competition from Kodak and Fuji, the computer maker's offerings never sold well.
It's no surprise, then, that Apple unceremoniously dumped its entire QuickTake product line around 1997—likely a victim of Steve Jobs' famous house cleaning.
Apple Adjustable Keyboard
Syndrome Me Mac Os X
At some point in the early 1990s, it became legally fashionable to be concerned with computer ergonomics. Prolonged use of any keyboard can lead to hand and wrist strain, repetitive stress injuries, and carpal tunnel syndrome. As any responsible computer maker should (whispers the PR department), Apple decided to offer a 'healthy' alternative to its typical keyboards. So, in 1993, the company released the Apple Adjustable Keyboard, which looked, more or less, like a typical Apple keyboard split in two (but with a honkin' big space bar). In the middle of the split was a hinge that allowed users to position the two halves of the keyboard at the most comfortable angle for them.
Unfortunately for Apple, the most comfortable position for the Apple Adjustable Keyboard was as far away from the user as possible, dooming Apple's ergonomic wonder to obscurity.
Mac OS X Server 1.0
'Ha! OS X Server!' you scoff, 'I remember that!' Well, do you remember the first version of OS X Server? You know, the one with the Rhapsody interface?
In a time before Apple's flashy, translucent, candy-colored Aqua, in a time before OS X's consumer rollout, Apple badly needed a strong server OS.
Eager to take those first steps into a more stable world, Apple released its first production OS based on NeXT technology in March 1999: Mac OS X Server 1.0. It looked, on the surface, a lot like Mac OS 8. But digging a little further, you'd notice the larger icons, the OPENSTEP Workspace Manager instead of a Finder, and…what's this? A Unix-like shell console? Clearly all was not normal in the world of Mac.
Like the later releases of OS X, OS X Server 1.0 was based on a Unix core, owing to its NeXT heritage, but it lacked the graphical eye candy of Aqua and the iconic Dock. Online casino winners. Soon, the OS X Public Beta would come along and sweep the last vestiges of Mac OS 8's platinum stylings away for good, leaving this OS X Server 1.0 a unique curiosity in the history of Apple.
Apple PC 5.25-inch Drive
CT
The most common findings of MAC infections include 1,2: The art of shattering mac os.
- bronchiectasis and bronchial wall thickening: most common findings
- small centrilobular nodules and tree-in-bud appearance
- patchy consolidation
- a predilection for the right middle lobe and lingula is seen particularly in elderly white women
- pleural thickening may be seen, usually adjacent to parenchymal change
- upper lobe cavitation may also be seen, although it is more characteristic of pulmonary tuberculosis
Treatment and prognosis
Many treatment regimes have been published, with no clear gold-standard evident, although as is the case with pulmonary TB, multi-drug therapy is ideal to avoid resistance 2.
In patients who are unable to tolerate medical management, and who have an adequate respiratory reserve, resection of affected portions of the lung may be undertaken. Complications of surgery include bronchopleural fistulas, hemoptysis and empyema2.
In patients in whom isolates of MAC are not clearly pathogenic, follow-up is required, keeping in mind that evidence of radiographic progression may take a number of years to be convincing 3.
Prognosis depends on the form of the disease. In the upper lobe cavitary form, lung destruction is usually progressive and can lead to respiratory failure and death if successful treatment is not instituted.
In patients with the nodular bronchiectatic form (Lady Windermere syndrome) the disease is much more indolent, however, eventually, this form may also lead to enough parenchymal damage to result in respiratory failure and death 3.
Differential diagnosis
- Mycobacterium tuberculosis pulmonary infection:
- bronchiectasis is less commonly the dominant feature 1
- changes usually in the upper lobes 1
- see other causes of bronchiectasis
The underlying pulmonary abnormality (e.g. COPD, pneumoconiosis) may dominate the radiographic appearance.
- 1. Primack SL, Logan PM, Hartman TE et-al. Pulmonary tuberculosis and Mycobacterium avium-intracellulare: a comparison of CT findings. Radiology. 1995;194 (2): 413-7. Radiology (abstract) - Pubmed citation
- 2. Field SK, Fisher D, Cowie RL. Mycobacterium avium complex pulmonary disease in patients without HIV infection. Chest. 2004;126 (2): 566-81. doi:10.1378/chest.126.2.566 - Pubmed citation
- 3. Müller NL, Franquet T, Lee KS et-al. Imaging of pulmonary infections. Lippincott Williams & Wilkins. (2007) ISBN:078177232X. Read it at Google Books - Find it at Amazon
- 4. Hartman TE, Jensen E, Tazelaar HD et-al. CT findings of granulomatous pneumonitis secondary to Mycobacterium avium-intracellulare inhalation: 'hot tub lung'. AJR Am J Roentgenol. 2007;188 (4): 1050-3. doi:10.2214/AJR.06.0546 - Pubmed citation
- 5. Kim TS, Koh WJ, Han J et-al. Hypothesis on the evolution of cavitary lesions in nontuberculous mycobacterial pulmonary infection: thin-section CT and histopathologic correlation. AJR Am J Roentgenol. 2005;184 (4): 1247-52. doi:10.2214/ajr.184.4.01841247 - Pubmed citation
- 6. Martinez S, McAdams HP, Batchu CS. The many faces of pulmonary nontuberculous mycobacterial infection. AJR Am J Roentgenol. 2007;189 (1): 177-86. doi:10.2214/AJR.07.2074 - Pubmed citation
Promoted articles (advertising)
With any company that's been around for more than 30 years—and with as many interesting, creative, and varied ideas Apple has had—there are bound to be a few Apple products that have slipped through history's cracks. New free slot machines. Along with its incredible successes, Apple has made its rightful share of clunkers and obscure products that quickly sunk to the bottom of the deep and vast ocean of public memory.
Come with us now as we explore these depths and dredge up five Apple products that probably won't get the blowout anniversary treatment on the virtual pages of Macworld.com
QuickTake 100
Apple Computer—known for its groundbreaking work with PCs, PDAs, and…digital cameras? Indeed, 1994 saw the release of Apple's QuickTake 100, one of the first consumer digital cameras in the US. The inaugural model of the QuickTake series debuted with an awkward form factor that resembled a one-eyed pair of futuristic binoculars. House of fun money.
Capable of storing eight photos at 640-by-480 resolution (or 32 at 320-by-240) on a whopping 1MB of internal flash memory, it was obviously primitive by today's standards. Apple released more powerful members of the QuickTake family over the next few years, but under the weight of competition from Kodak and Fuji, the computer maker's offerings never sold well.
It's no surprise, then, that Apple unceremoniously dumped its entire QuickTake product line around 1997—likely a victim of Steve Jobs' famous house cleaning.
Apple Adjustable Keyboard
Syndrome Me Mac Os X
At some point in the early 1990s, it became legally fashionable to be concerned with computer ergonomics. Prolonged use of any keyboard can lead to hand and wrist strain, repetitive stress injuries, and carpal tunnel syndrome. As any responsible computer maker should (whispers the PR department), Apple decided to offer a 'healthy' alternative to its typical keyboards. So, in 1993, the company released the Apple Adjustable Keyboard, which looked, more or less, like a typical Apple keyboard split in two (but with a honkin' big space bar). In the middle of the split was a hinge that allowed users to position the two halves of the keyboard at the most comfortable angle for them.
Unfortunately for Apple, the most comfortable position for the Apple Adjustable Keyboard was as far away from the user as possible, dooming Apple's ergonomic wonder to obscurity.
Mac OS X Server 1.0
'Ha! OS X Server!' you scoff, 'I remember that!' Well, do you remember the first version of OS X Server? You know, the one with the Rhapsody interface?
In a time before Apple's flashy, translucent, candy-colored Aqua, in a time before OS X's consumer rollout, Apple badly needed a strong server OS.
Eager to take those first steps into a more stable world, Apple released its first production OS based on NeXT technology in March 1999: Mac OS X Server 1.0. It looked, on the surface, a lot like Mac OS 8. But digging a little further, you'd notice the larger icons, the OPENSTEP Workspace Manager instead of a Finder, and…what's this? A Unix-like shell console? Clearly all was not normal in the world of Mac.
Like the later releases of OS X, OS X Server 1.0 was based on a Unix core, owing to its NeXT heritage, but it lacked the graphical eye candy of Aqua and the iconic Dock. Online casino winners. Soon, the OS X Public Beta would come along and sweep the last vestiges of Mac OS 8's platinum stylings away for good, leaving this OS X Server 1.0 a unique curiosity in the history of Apple.
Apple PC 5.25-inch Drive
As a minor nod towards achieving some form of IBM PC compatibility, Apple released its own 360K double-density 5.25-inch floppy drive for the Macintosh in the late 1980s. The sleek, low-profile external drive (rendered in the snow white design language of the day) required a special controller card to use, and it never achieved much widespread use. (After all, most people were choosing Macs to get away from IBM PC-compatibles—why bring them any closer than you have to?)
Apple Network Server
Pop quiz: What's the only Apple computer officially designed to never, ever run an Apple OS? If you said 'the Apple Network Server,' then you probably read the header of this section.
Introduced in 1996, this obscure, PowerPC-based behemoth filled a gaping hole in Apple's high-end product line: that of industrial-strength network server—a task that Apple's Mac OS just wasn't capable of at the time. Jesters nightmare mac os. Interestingly, Apple turned to IBM's AIX (a Unix derivative) as the operating system of choice, likely because the ANS's underlying hardware resembled IBM PowerPC-based servers of the day. It seems strange, but this beast was never a member of the Macintosh family; in fact, it contained a ROM that prevented the booting of Mac OS all together. If you ever see one of these sitting on a street corner, take it in and show it your sympathy, as they're quite rare.
