Mrs. X frantically came to the office at 10:30 in the morning and apologized for not having an appointment but demanded that her 7 year old son, Bobby, be seen. She was obviously upset but she wouldn’t tell the nurses what the issue was, other than he had a rash. The nurses put him in an examining room and asked me to see him.
When I entered the room, she shook her head and said the school called her to come and pick Bobby up because they thought he had either scabies or chicken pox. Apparently he was sitting in class and constantly itching his lower abdomen and when the teacher asked him what was bothering him, he lifted up his shirt and revealed about 10 pimple-like pustules. She gasped and sent him right off to the school nurse thinking that he had scabies. The nurse wasn’t convinced that it was scabies, but was more concerned that it might be chicken pox. Regardless, the called Bobby’s mom and asked her to take him home until this was sorted out.
She was mortified that this could be scabies. “That sounds just awful,” she said in an indignant voice, “We are compulsive about cleanliness and hygiene and Bobby bathes every day!” Then she went on to remind me that he had 2 chicken pox vaccines by kindergarten and really had no other symptoms. “How could this possibly be chicken pox,” she pondered.
Bobby was calmly sitting there playing a video game, undaunted by the whole situation. He did not have a fever and seemed just fine. I had him sit on the examining table and took off his shirt. I did a thorough exam and everything was completely normal except for around 10 pimple-like lesions on his lower abdomen, more on the right side. They were red and slightly raised, about 3-4 mm in size, and most of them had a central pustule, or head. There were some scratch marks from him itching them. There were no such lesions anywhere else, especially not in between the fingers or toes, and not along the waistline where one would expect to see scabies. All of the lesions seemed to be at about the same stage of progression, which is unlike chicken pox. Chicken pox erupts in “crops” and when you look at an area of skin with chicken pox, there are all different stages of lesions at a given time. Some are just starting, some are blistered or vesicles with fluid, some have started to crust and some have started to scab. Bobby’s lesions were all very similar and were “just there”.
I tried to allay mom’s fears by stating emphatically that Bobby did NOT have chicken pox nor did he have scabies. She sighed a big sigh of relief, and then asked what it was.
I asked if he had been swimming or in a spa recently. She said no, that they didn’t have a pool and it was still too cold for that. I asked Bobby and he agreed with mom. Then he said, “Well, I did go in a Jacuzzi last Friday when I went to my friend’s birthday party. We all borrowed swimming trunks and were in the Jacuzzi for about an hour.” His mom said, “ I didn’t know that, but that was 5 days ago. Isn’t it a bit late for this rash now,” she asked.
I told her that Bobby had Hot Tub Folliculitis and the timing was perfect for this. While she was relieved that he didn’t have scabies or chicken pox, she was even more concerned saying that this sounded just as dreadful. I then went on to explain to her what this all meant.
Hot tub Folliculitis is a localized infection of the hair follicle caused by a specific bacteria, Pseudomonas aeruginosa, which is a water-loving organism. It can thrive in swimming pools, spas, water parks or hot tubs when the conditions are just right. This would include a high pH, or not enough chlorine. The CDC recommends that for pools, spas and hot tubs, the pH should be kept between 7.2 and 7.8. The chlorine level should be between 1-3 mg/liter. Any deviation from that provides an environment that is optimal for the Pseudomonas to thrive.
The folliculitis typically shows up anywhere from 8 hours to 5 days after exposure. It starts as small red macule that may become raised with a central pustule or small head. The typical lesion is 2 -10 mm in size and doesn’t follow any particular pattern or distribution. They tend to cluster in areas where the bathing suits cover the skin or in skin fold areas. They do not typically spread and they usually self resolve in 7-10 days. They may itch or even be a bit uncomfortable but this is nothing more than a nuisance. Most lesions will spontaneously resolve in 7-10 days but they may leave a residual hyperpigmented area that slowly goes away in a matter of months.
There is no human-to-human transmission so it is not contagious. While the lesions will self-resolve, a topical antibiotic such as Gentamicin may shorten the course of the individual lesion.
I told mom that the first report of this goes back to 1975 where an outbreak was traced to a hot tub. It is something we typically see a lot of in the summer months for obvious reasons. I assured her that Bobby would be just fine and she did ask for a prescription for the topical antibiotic as she wanted to minimize the risk of the hyperpigmented areas and this seemed most reasonable.
Both mom and Bobby were pleased, and in a calculating voice he asked her if they could stop and get fast food for lunch “on the way home”. She looked at him and with a wry smile announced that, “After I get a note from Dr. Theriot stating that you are not contagious, I am taking you right back to school. Don’t you have a Math test this afternoon?” I’ve never seen a smile disappear from a face so quickly!