What's the difference between に至っては and ときたら


I was reviewing some N1 Grammar when I noticed that both of these seem to
translate to "when it comes to", "as for" Is there any difference between the
two in terms of nuances? I'd really appreciate it if you can cite sources.

<https://japanesetest4you.com/flashcard/learn-
jlpt-n1-grammar-%E3%81%A8%E3%81%8D%E3%81%9F%E3%82%89-tokitara/>

<https://japanesetest4you.com/flashcard/learn-
jlpt-n1-grammar-%E3%81%AB%E3%81%84%E3%81%9F%E3%81%A3%E3%81%A6%E3%81%AF-ni-
itatte-wa/>




Xに至っては has the nuance of "moreover", "on top of that", "what's worse/more",
etc. It means X is even more extraordinary than what was already mentioned.
The examples in the linked page lack the context, but 美智子に至ってはうきうきしているようだった
makes little sense without a proper previous context, like:

> その悲しいニュースを聞いても、太郎は特に悲しんでいないようだった。美智子 **に至っては** うきうきしているようだった。

Xに至っては also means "now that we have reached X", "(we're already) at this
point", etc. 「ここに至っては、もう祈ることしかできない。」

Xときたら is just a colloquial topic marker, and the predicate is usually
something bad. It's typically used to speak ill of something/someone, as shown
in the examples in the link.




Xに至っては has the nuance of "moreover", "on top of that", "what's worse/more",
etc. It means X is even more extraordinary than what was already mentioned.
The examples in the linked page lack the context, but 美智子に至ってはうきうきしているようだった
makes little sense without a proper previous context, like:

> その悲しいニュースを聞いても、太郎は特に悲しんでいないようだった。美智子 **に至っては** うきうきしているようだった。

Xに至っては also means "now that we have reached X", "(we're already) at this
point", etc. 「ここに至っては、もう祈ることしかできない。」

Xときたら is just a colloquial topic marker, and the predicate is usually
something bad. It's typically used to speak ill of something/someone, as shown
in the examples in the link.

