We are all familiar with the story of Alexander Fleming, returning from holiday in 1928 to discover his S. aureus culture plates had been contaminated. An assistant, carelessly, had left a window open in the laboratory; Penicillium chrysogenum, no doubt sensing an opportunity to become famous, went on a rampage, killing countless bacteria. Fleming realised what had happened and since then penicillin has saved innumerable lives.
You might not know that P. chrysogenum has an older cousin who first arrived on the scene long before that. Around a thousand years ago, a shepherd abandoned his cheese sandwich in a cave, to take a second look at a young lady who was passing by. He returned later (cheese sandwiches being in short supply back then) to find his snack had become mouldy. Roquefort was born, thanks to the best efforts of P. roqueforti. I'll spare you the similarly authenticated tales of how Camembert and Gorgonzola came into being. It can be humbling to realise how much we owe to a family of moulds.
However, there is a dark sheep in this family.
The patient lies quietly in the HIV ward, which is aptly-named. He is staring at the ceiling in an isolated, six bed bay. We interrupt his thoughts. There are only three of us, which probably makes a welcome change for patients who are used to more than a dozen doctors and nurses on each ward round. He's known to have HIV, but he isn't receiving anti-retroviral drugs. For the last month he's been tired, coughing, losing weight, feverish. His chest X-ray is normal. He's very anaemic, and his liver and spleen are massively enlarged. He's had frequent nose-bleeds and he's obviously uncomfortable while we examine him. An unusual rash, reminiscent of chickenpox, covers him from head to toe.
The Consultant picks my brains: how can I explain all these findings? I'm quite proud to have come up with a half-dozen suggestions, even if they turn out to all be wrong. Which they do. I begin to plead ignorance. "Penicillium marneffei", I'm told. A fungus present only in South-East Asia which causes disease only in the immuno-compromised. I had strategically decided not to learn about it for finals, but it seems that the Penicillium family is greater than I had ever suspected.
A course of itraconazole and amphotericin B will cure him of his penicilliosis soon enough, but he'll still be left with the HIV. And before we curse the virus, it's worth noting that it has quickly become one of the most important tools in molecular biology today. These microbes just can't decide whether to be good or bad.
Information on P.marneffei
You might not know that P. chrysogenum has an older cousin who first arrived on the scene long before that. Around a thousand years ago, a shepherd abandoned his cheese sandwich in a cave, to take a second look at a young lady who was passing by. He returned later (cheese sandwiches being in short supply back then) to find his snack had become mouldy. Roquefort was born, thanks to the best efforts of P. roqueforti. I'll spare you the similarly authenticated tales of how Camembert and Gorgonzola came into being. It can be humbling to realise how much we owe to a family of moulds.
However, there is a dark sheep in this family.
The patient lies quietly in the HIV ward, which is aptly-named. He is staring at the ceiling in an isolated, six bed bay. We interrupt his thoughts. There are only three of us, which probably makes a welcome change for patients who are used to more than a dozen doctors and nurses on each ward round. He's known to have HIV, but he isn't receiving anti-retroviral drugs. For the last month he's been tired, coughing, losing weight, feverish. His chest X-ray is normal. He's very anaemic, and his liver and spleen are massively enlarged. He's had frequent nose-bleeds and he's obviously uncomfortable while we examine him. An unusual rash, reminiscent of chickenpox, covers him from head to toe.
The Consultant picks my brains: how can I explain all these findings? I'm quite proud to have come up with a half-dozen suggestions, even if they turn out to all be wrong. Which they do. I begin to plead ignorance. "Penicillium marneffei", I'm told. A fungus present only in South-East Asia which causes disease only in the immuno-compromised. I had strategically decided not to learn about it for finals, but it seems that the Penicillium family is greater than I had ever suspected.
A course of itraconazole and amphotericin B will cure him of his penicilliosis soon enough, but he'll still be left with the HIV. And before we curse the virus, it's worth noting that it has quickly become one of the most important tools in molecular biology today. These microbes just can't decide whether to be good or bad.
Information on P.marneffei
Another great post, Richard.
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