Here's a few more :)
AAMOF = as a matter of fact
AS = Ankylosing Spondylitis
ASAP = as soon as possible
B = back
BAK = back at keyboard
BBL = be back later
BBS = be back soon
BBFN = bye bye for now
BFN = bye for now
BRB = be right back
BRBGGP = be right back gotta go potty
BTW = by the way
CRAFT = can't remember a fricking thing
CRP = C-reactive protein
(Concentrations of this in the blood indicate inflammation and disease activity.)CRS = can't remember stuff
CU = see you
CUL8R = see you later
CYA = see ya
ESR = Erythrocyte Sedimentation Rate
(A blood test which can help in the diagnosis of arthritis.)FUBAR = fouled up beyond all recognition
FYI = for your information
GMTA = great minds think alike
GF = Gluten Free
GP = general practitioner
GTG = got to go
HB = hurry back
HLA-B27 = One of the genes which has been associated with ankylosing spondylitis
IMHO = in my humble opinion
IMNSHO = in my not so humble opinion
IMO = in my opinion
JK = joke
J/K = just kidding
K = okay
LOL = laughing out loud
LOLROF = laughing out load, rolling on floor
LMAO = laughing my a** off
LSD = Low Starch Diet
LTNS = long time no see
MRI = Magnetic Resonance Imaging
A scan MYOB = mind your own business
NP = no problem
NSD = No Starch Diet
OIC = oh I see
PCP = primary care physician
PsA = psoriatic arthritis
ROF = rolling on floor
ROTF = rolling on the floor
ROFLMAO = rolling on floor laughing my a** off
ROFLOL = rolling on floor laughing out loud
SNAFU = situation normal all fouled up
SOS = same old stuff
TTFN = ta ta for now
TTYL = talk to you later
TU = thank you
TY = thank you
WB = welcome back
WRT = with respect/regard to
WTG = way to go
YW = your welcome
Loz 
"
Think like a wise man but communicate in the language of the people." William Butler Yeats (1865 - 1939)